diff --git a/ivatar/ivataraccount/auth_models.py b/ivatar/ivataraccount/auth_models.py
index 1d839a7..c6e2d44 100644
--- a/ivatar/ivataraccount/auth_models.py
+++ b/ivatar/ivataraccount/auth_models.py
@@ -70,18 +70,32 @@ class BruteForceAttempt(models.Model):
         if self.is_blocked:
             return True
 
-        # Reset attempts if outside time window
-        if timezone.now() - self.first_attempt > timezone.timedelta(
-            minutes=time_window_minutes
-        ):
-            self.attempt_count = 1
-            self.first_attempt = timezone.now()
-            self.is_blocked = False
-            self.save()
+        # Check if outside time window
+        time_diff = timezone.now() - self.first_attempt
+        time_window = timezone.timedelta(minutes=time_window_minutes)
+
+        if time_diff > time_window:
+            # Time window has expired, should not block
             return False
 
         return self.attempt_count >= max_attempts
 
+    def reset_if_expired(self, time_window_minutes: int = 15) -> bool:
+        """
+        Reset attempt if time window has expired
+        Returns True if reset was performed, False otherwise
+        """
+        time_diff = timezone.now() - self.first_attempt
+        time_window = timezone.timedelta(minutes=time_window_minutes)
+
+        if time_diff > time_window:
+            self.attempt_count = 0
+            self.first_attempt = timezone.now()
+            self.is_blocked = False
+            self.save()
+            return True
+        return False
+
     def increment_attempt(self) -> None:
         """Increment the attempt count"""
         self.attempt_count += 1
diff --git a/ivatar/ivataraccount/auth_views.py b/ivatar/ivataraccount/auth_views.py
index 6d8cc54..a3c23c5 100644
--- a/ivatar/ivataraccount/auth_views.py
+++ b/ivatar/ivataraccount/auth_views.py
@@ -46,6 +46,9 @@ class ExternalAuthView(View):
                 defaults={"attempt_count": 0},
             )
 
+        # Reset attempts if time window has expired
+        brute_force_attempt.reset_if_expired()
+
         if brute_force_attempt.should_block():
             return JsonResponse(
                 {
@@ -70,7 +73,16 @@ class ExternalAuthView(View):
 
         # If group is specified, check if user is in that group
         if group:
-            if not request.user.groups.filter(name=group).exists():
+            # Special handling for 'admin' group: also check if user is superuser
+            if group == "admin":
+                is_in_group = (
+                    request.user.groups.filter(name=group).exists()
+                    or request.user.is_superuser
+                )
+            else:
+                is_in_group = request.user.groups.filter(name=group).exists()
+
+            if not is_in_group:
                 brute_force_attempt.increment_attempt()
                 return JsonResponse(
                     {
diff --git a/ivatar/ivataraccount/test_auth_models.py b/ivatar/ivataraccount/test_auth_models.py
index 1268e21..d0623f2 100644
--- a/ivatar/ivataraccount/test_auth_models.py
+++ b/ivatar/ivataraccount/test_auth_models.py
@@ -13,6 +13,7 @@ os.environ["DJANGO_SETTINGS_MODULE"] = "ivatar.settings"
 django.setup()
 
 from ivatar.ivataraccount.auth_models import AuthToken, BruteForceAttempt
+from ivatar.utils import random_string
 
 
 class AuthTokenTestCase(TestCase):
@@ -22,8 +23,11 @@ class AuthTokenTestCase(TestCase):
 
     def setUp(self):
         """Set up test data"""
+        self.username = random_string()
+        self.password = random_string()
+        self.email = f"{random_string()}@{random_string()}.com"
         self.user = User.objects.create_user(
-            username="testuser", password="testpass123", email="test@example.com"
+            username=self.username, password=self.password, email=self.email
         )
 
     def test_auth_token_creation(self):
@@ -89,8 +93,11 @@ class BruteForceAttemptTestCase(TestCase):
 
     def setUp(self):
         """Set up test data"""
+        self.username = random_string()
+        self.password = random_string()
+        self.email = f"{random_string()}@{random_string()}.com"
         self.user = User.objects.create_user(
-            username="testuser", password="testpass123", email="test@example.com"
+            username=self.username, password=self.password, email=self.email
         )
         self.ip_address = "127.0.0.1"
         self.user_agent = "Mozilla/5.0 Test Browser"
@@ -111,7 +118,7 @@ class BruteForceAttemptTestCase(TestCase):
 
     def test_brute_force_attempt_creation_unauthenticated_user(self):
         """Test BruteForceAttempt creation for unauthenticated user"""
-        username = "testusername"
+        username = random_string()
         attempt = BruteForceAttempt.objects.create(
             username=username, ip_address=self.ip_address, user_agent=self.user_agent
         )
@@ -164,9 +171,12 @@ class BruteForceAttemptTestCase(TestCase):
         # Should reset and not block (outside 15-minute window)
         self.assertFalse(attempt.should_block(max_attempts=5, time_window_minutes=15))
 
+        # Reset the attempt count using the new method
+        attempt.reset_if_expired(time_window_minutes=15)
+
         # Should have reset attempt count
         attempt.refresh_from_db()
-        self.assertEqual(attempt.attempt_count, 1)
+        self.assertEqual(attempt.attempt_count, 0)
         self.assertFalse(attempt.is_blocked)
 
     def test_should_block_when_explicitly_blocked(self):
@@ -212,10 +222,11 @@ class BruteForceAttemptTestCase(TestCase):
         self.assertEqual(str(attempt_with_user), expected_str_user)
 
         # Test with username only
+        test_username = random_string()
         attempt_with_username = BruteForceAttempt.objects.create(
-            username="testusername", ip_address=self.ip_address, attempt_count=2
+            username=test_username, ip_address=self.ip_address, attempt_count=2
         )
-        expected_str_username = "Brute force attempt for testusername (2 attempts)"
+        expected_str_username = f"Brute force attempt for {test_username} (2 attempts)"
         self.assertEqual(str(attempt_with_username), expected_str_username)
 
         # Test with IP only
@@ -227,15 +238,16 @@ class BruteForceAttemptTestCase(TestCase):
 
     def test_unique_together_constraint(self):
         """Test unique_together constraint"""
+        test_username = random_string()
         # Create first attempt
         BruteForceAttempt.objects.create(
-            user=self.user, username="testuser", ip_address=self.ip_address
+            user=self.user, username=test_username, ip_address=self.ip_address
         )
 
         # Try to create duplicate (should fail)
         with self.assertRaises(Exception):  # IntegrityError
             BruteForceAttempt.objects.create(
-                user=self.user, username="testuser", ip_address=self.ip_address
+                user=self.user, username=test_username, ip_address=self.ip_address
             )
 
     def test_get_or_create_behavior(self):
diff --git a/ivatar/ivataraccount/test_auth_views.py b/ivatar/ivataraccount/test_auth_views.py
index b60ca97..151e2a0 100644
--- a/ivatar/ivataraccount/test_auth_views.py
+++ b/ivatar/ivataraccount/test_auth_views.py
@@ -105,6 +105,102 @@ class ExternalAuthViewTestCase(TestCase):
         self.assertEqual(data["reason"], "not_in_group")
         self.assertEqual(data["message"], f"User is not in group: {self.group_name}")
 
+    def test_external_auth_admin_group_superuser_access(self):
+        """Test that superusers can access admin group even without being in admin group"""
+        # Make the existing user a superuser
+        self.user.is_superuser = True
+        self.user.save()
+
+        # Login as superuser
+        self.client.login(username=self.username, password=self.password)
+
+        # Try to access admin group (superuser should have access even without being in admin group)
+        response = self.client.get("/accounts/api/external/admin/")
+
+        self.assertEqual(response.status_code, 200)
+        data = json.loads(response.content)
+        self.assertTrue(data["authenticated"])
+        self.assertIn("token", data)
+
+        # Verify token was created for superuser
+        token_obj = AuthToken.objects.get(token=data["token"])
+        self.assertEqual(token_obj.user, self.user)
+
+    def test_external_auth_admin_group_regular_user_in_admin_group(self):
+        """Test that regular users in admin group can access admin group"""
+        # Create admin group
+        admin_group = Group.objects.create(name="admin")
+
+        # Add user to admin group
+        self.user.groups.add(admin_group)
+
+        # Login as user
+        self.client.login(username=self.username, password=self.password)
+
+        # Try to access admin group
+        response = self.client.get("/accounts/api/external/admin/")
+
+        self.assertEqual(response.status_code, 200)
+        data = json.loads(response.content)
+        self.assertTrue(data["authenticated"])
+        self.assertIn("token", data)
+
+    def test_external_auth_admin_group_regular_user_not_in_admin_group(self):
+        """Test that regular users not in admin group cannot access admin group"""
+        # Login as user (not in admin group)
+        self.client.login(username=self.username, password=self.password)
+
+        # Try to access admin group
+        response = self.client.get("/accounts/api/external/admin/")
+
+        self.assertEqual(response.status_code, 403)
+        data = json.loads(response.content)
+        self.assertFalse(data["authenticated"])
+        self.assertEqual(data["reason"], "not_in_group")
+        self.assertEqual(data["message"], "User is not in group: admin")
+
+    def test_external_auth_admin_group_superuser_and_in_admin_group(self):
+        """Test that superusers who are also in admin group can access admin group"""
+        # Create admin group
+        admin_group = Group.objects.create(name="admin")
+
+        # Make the existing user a superuser
+        self.user.is_superuser = True
+        self.user.save()
+
+        # Add user to admin group as well
+        self.user.groups.add(admin_group)
+
+        # Login as superuser
+        self.client.login(username=self.username, password=self.password)
+
+        # Try to access admin group
+        response = self.client.get("/accounts/api/external/admin/")
+
+        self.assertEqual(response.status_code, 200)
+        data = json.loads(response.content)
+        self.assertTrue(data["authenticated"])
+        self.assertIn("token", data)
+
+    def test_external_auth_non_admin_group_normal_behavior(self):
+        """Test that non-admin groups work normally (no superuser privilege)"""
+        # Make the existing user a superuser
+        self.user.is_superuser = True
+        self.user.save()
+
+        # Login as superuser
+        self.client.login(username=self.username, password=self.password)
+
+        # Try to access a different group that the user is NOT in (superuser should NOT have automatic access)
+        different_group = random_string()
+        response = self.client.get(f"/accounts/api/external/{different_group}/")
+
+        self.assertEqual(response.status_code, 403)
+        data = json.loads(response.content)
+        self.assertFalse(data["authenticated"])
+        self.assertEqual(data["reason"], "not_in_group")
+        self.assertEqual(data["message"], f"User is not in group: {different_group}")
+
     def test_external_auth_nonexistent_group(self):
         """Test external auth endpoint with non-existent group"""
         nonexistent_group = random_string()
@@ -230,15 +326,16 @@ class ExternalAuthViewTestCase(TestCase):
 
     def test_external_auth_brute_force_tracking_by_ip_and_username(self):
         """Test that brute force attempts are tracked by IP and username for unauthenticated users"""
+        test_username = random_string()
         # Make requests with username parameter
         for i in range(3):
             response = self.client.get(
-                "/accounts/api/external/", {"username": "testuser"}
+                "/accounts/api/external/", {"username": test_username}
             )
             self.assertEqual(response.status_code, 401)
 
         # Check that attempt is tracked by username and IP
-        attempt = BruteForceAttempt.objects.get(username="testuser")
+        attempt = BruteForceAttempt.objects.get(username=test_username)
         self.assertEqual(attempt.attempt_count, 3)
         self.assertIsNotNone(attempt.ip_address)
 
diff --git a/ivatar/ivataraccount/test_brute_force.py b/ivatar/ivataraccount/test_brute_force.py
index 2dace56..03636d4 100644
--- a/ivatar/ivataraccount/test_brute_force.py
+++ b/ivatar/ivataraccount/test_brute_force.py
@@ -83,10 +83,11 @@ class BruteForceProtectionTestCase(TestCase):
 
     def test_brute_force_protection_with_username_parameter(self):
         """Test brute force protection with username parameter for unauthenticated users"""
+        test_username = random_string()
         # Make requests with username parameter
         for i in range(7):
             response = self.client.get(
-                "/accounts/api/external/", {"username": "testuser"}
+                "/accounts/api/external/", {"username": test_username}
             )
 
             if i < 5:
@@ -97,7 +98,7 @@ class BruteForceProtectionTestCase(TestCase):
                 self.assertEqual(response.status_code, 429)
 
         # Verify brute force attempt was created with username
-        attempt = BruteForceAttempt.objects.get(username="testuser")
+        attempt = BruteForceAttempt.objects.get(username=test_username)
         self.assertEqual(attempt.attempt_count, 5)
         self.assertTrue(attempt.is_blocked)
         self.assertIsNotNone(attempt.ip_address)
@@ -118,6 +119,7 @@ class BruteForceProtectionTestCase(TestCase):
         attempt = BruteForceAttempt.objects.get(user=self.user)
         old_time = timezone.now() - timezone.timedelta(minutes=20)
         attempt.first_attempt = old_time
+        attempt.last_attempt = old_time  # Also set last_attempt to old time
         attempt.save()
 
         # Next request should reset and succeed
@@ -131,7 +133,11 @@ class BruteForceProtectionTestCase(TestCase):
 
     def test_brute_force_protection_successful_auth_resets_attempts(self):
         """Test that successful authentication resets brute force attempts"""
-        self.client.login(username="testuser", password="testpass123")
+        # Login with the correct credentials from setUp
+        login_success = self.client.login(
+            username=self.username, password=self.password
+        )
+        self.assertTrue(login_success, "Login should succeed")
 
         # Make some requests to build up attempt count
         for i in range(3):
@@ -145,9 +151,10 @@ class BruteForceProtectionTestCase(TestCase):
 
     def test_brute_force_protection_different_users_independent(self):
         """Test that brute force protection is independent for different users"""
+        user2_password = random_string()
         user2 = User.objects.create_user(
             username=random_string(),
-            password=random_string(),
+            password=user2_password,
             email=f"{random_string()}@{random_string()}.com",
         )
 
@@ -160,7 +167,11 @@ class BruteForceProtectionTestCase(TestCase):
         self.assertEqual(response.status_code, 429)
 
         # Second user should still be able to authenticate
-        self.client.login(username=user2.username, password=user2.password)
+        login_success = self.client.login(
+            username=user2.username, password=user2_password
+        )
+        self.assertTrue(login_success, "Second user login should succeed")
+
         response = self.client.get("/accounts/api/external/")
         self.assertEqual(response.status_code, 200)
 
@@ -199,7 +210,10 @@ class BruteForceProtectionTestCase(TestCase):
 
     def test_brute_force_protection_user_agent_tracking(self):
         """Test that user agent is properly tracked"""
-        self.client.login(username="testuser", password="testpass123")
+        login_success = self.client.login(
+            username=self.username, password=self.password
+        )
+        self.assertTrue(login_success, "Login should succeed")
 
         # Make request with custom user agent
         response = self.client.get(
@@ -214,7 +228,10 @@ class BruteForceProtectionTestCase(TestCase):
 
     def test_brute_force_protection_custom_thresholds(self):
         """Test brute force protection with custom thresholds"""
-        self.client.login(username="testuser", password="testpass123")
+        login_success = self.client.login(
+            username=self.username, password=self.password
+        )
+        self.assertTrue(login_success, "Login should succeed")
 
         # Create attempt with custom threshold
         attempt = BruteForceAttempt.objects.create(user=self.user, attempt_count=2)
@@ -235,12 +252,26 @@ class BruteForceProtectionTestCase(TestCase):
         attempt = BruteForceAttempt.objects.create(
             user=self.user, attempt_count=10, first_attempt=old_time
         )
+        # Override last_attempt to be old as well (since save() sets it to now)
+        attempt.last_attempt = old_time
+        attempt.save()
 
-        # Should not block with 5-minute window (outside window)
-        self.assertFalse(attempt.should_block(max_attempts=5, time_window_minutes=5))
+        # Test with 5-minute window (should not block - outside window)
+        should_block_5min = attempt.should_block(max_attempts=5, time_window_minutes=5)
+        self.assertFalse(should_block_5min)
 
-        # Should block with 15-minute window (within window)
-        self.assertTrue(attempt.should_block(max_attempts=5, time_window_minutes=15))
+        # Create a fresh attempt for the 15-minute test to avoid side effects
+        attempt2 = BruteForceAttempt.objects.create(
+            user=self.user, attempt_count=10, first_attempt=old_time
+        )
+        attempt2.last_attempt = old_time
+        attempt2.save()
+
+        # Test with 15-minute window (should block - within window)
+        should_block_15min = attempt2.should_block(
+            max_attempts=5, time_window_minutes=15
+        )
+        self.assertTrue(should_block_15min)
 
     def test_brute_force_protection_explicit_blocking(self):
         """Test explicit blocking of brute force attempts"""
@@ -279,15 +310,16 @@ class BruteForceProtectionTestCase(TestCase):
 
     def test_brute_force_protection_unique_constraints(self):
         """Test unique constraints for brute force attempts"""
+        test_username = random_string()
         # Create first attempt
         BruteForceAttempt.objects.create(
-            user=self.user, username="testuser", ip_address=self.ip_address
+            user=self.user, username=test_username, ip_address=self.ip_address
         )
 
         # Try to create duplicate (should fail)
         with self.assertRaises(Exception):  # IntegrityError
             BruteForceAttempt.objects.create(
-                user=self.user, username="testuser", ip_address=self.ip_address
+                user=self.user, username=test_username, ip_address=self.ip_address
             )
 
     def test_brute_force_protection_mixed_authentication_states(self):
@@ -295,12 +327,15 @@ class BruteForceProtectionTestCase(TestCase):
         # Start unauthenticated
         for i in range(3):
             response = self.client.get(
-                "/accounts/api/external/", {"username": "testuser"}
+                "/accounts/api/external/", {"username": self.username}
             )
             self.assertEqual(response.status_code, 401)
 
         # Switch to authenticated
-        self.client.login(username="testuser", password="testpass123")
+        login_success = self.client.login(
+            username=self.username, password=self.password
+        )
+        self.assertTrue(login_success, "Login should succeed")
 
         # Should still track by user now
         response = self.client.get("/accounts/api/external/")
diff --git a/ivatar/ivataraccount/test_token_auth.py b/ivatar/ivataraccount/test_token_auth.py
index ea57835..d0bf29f 100644
--- a/ivatar/ivataraccount/test_token_auth.py
+++ b/ivatar/ivataraccount/test_token_auth.py
@@ -15,6 +15,7 @@ django.setup()
 
 from ivatar.ivataraccount.auth_models import AuthToken
 from ivatar.ivataraccount.token_auth import TokenAuthenticationBackend
+from ivatar.utils import random_string
 
 
 class TokenAuthenticationBackendTestCase(TestCase):
@@ -24,8 +25,11 @@ class TokenAuthenticationBackendTestCase(TestCase):
 
     def setUp(self):
         """Set up test data"""
+        self.username = random_string()
+        self.password = random_string()
+        self.email = f"{random_string()}@{random_string()}.com"
         self.user = User.objects.create_user(
-            username="testuser", password="testpass123", email="test@example.com"
+            username=self.username, password=self.password, email=self.email
         )
         self.backend = TokenAuthenticationBackend()
         self.request = HttpRequest()
@@ -107,8 +111,8 @@ class TokenAuthenticationBackendTestCase(TestCase):
         user = self.backend.get_user(self.user.id)
 
         self.assertEqual(user, self.user)
-        self.assertEqual(user.username, "testuser")
-        self.assertEqual(user.email, "test@example.com")
+        self.assertEqual(user.username, self.username)
+        self.assertEqual(user.email, self.email)
 
     def test_get_user_with_invalid_id(self):
         """Test get_user with invalid user ID"""
@@ -174,8 +178,8 @@ class TokenAuthenticationBackendTestCase(TestCase):
         short_token = "abc"
         AuthToken.objects.create(token=short_token, user=self.user)
 
-        # Long token
-        long_token = "a" * 100
+        # Long token (within database limit)
+        long_token = "a" * 64
         AuthToken.objects.create(token=long_token, user=self.user)
 
         # Both should work