diff --git a/web/pgadmin/authenticate/oauth2.py b/web/pgadmin/authenticate/oauth2.py
index 201eb08e498..77f1a7b56c3 100644
--- a/web/pgadmin/authenticate/oauth2.py
+++ b/web/pgadmin/authenticate/oauth2.py
@@ -151,15 +151,12 @@ def login(self, form):
                 current_app.logger.exception(error_msg)
                 return False, gettext(error_msg)
 
-        additinal_claims = None
-        if 'OAUTH2_ADDITIONAL_CLAIMS' in self.oauth2_config[
-                self.oauth2_current_client]:
-            additinal_claims = self.oauth2_config[
-                self.oauth2_current_client
-            ]['OAUTH2_ADDITIONAL_CLAIMS']
+        current_oauth2_config = self.oauth2_config[self.oauth2_current_client]
+        additional_claims = current_oauth2_config['OAUTH2_ADDITIONAL_CLAIMS'] \
+            if 'OAUTH2_ADDITIONAL_CLAIMS' in current_oauth2_config else None
 
-        (valid, reason) = self.__is_additional_claims_valid(profile,
-                                                            additinal_claims)
+        valid, reason = self.__is_additional_claims_valid(profile,
+                                                          additional_claims)
 
         if not valid:
             return_msg = "The user is not authorized to login" \
@@ -225,23 +222,28 @@ def __auto_create_user(self, username, email):
 
         return True, {'username': username}
 
-    def __is_additional_claims_valid(self, profile, additional_claims):
+    @staticmethod
+    def __is_additional_claims_valid(profile, additional_claims):
+        valid = True
+        reason = "Claim match found. Authorizing"
+
         if additional_claims is None:
             reason = "Additional claim config is None, no check to do."
-            return (True, reason)
-        if not isinstance(additional_claims, dict):
-            reason = "Additional claim check config is not a dict."
-            return (False, reason)
-        if additional_claims.keys() is None:
-            reason = "Additional claim check config dict is empty."
-            return (False, reason)
+            return valid, reason
+        elif not isinstance(additional_claims, dict) or \
+                not bool(additional_claims):
+            reason = "Additional claim config is not a dict or a empty dict"
+            valid = False
+            return valid, reason
         for key in additional_claims.keys():
             claim = profile.get(key)
             if claim is None:
                 continue
             authorized_claims = additional_claims.get(key)
+            if isinstance(claim, str) and claim in authorized_claims:
+                return True, reason
             if any(item in authorized_claims for item in claim):
-                reason = "Claim match found. Authorizing"
-                return (True, reason)
-        reason = f"Profile does not have any of given additional claims."
-        return (False, reason)
+                return True, reason
+        valid = False
+        reason = "Profile does not have any of given additional claims."
+        return valid, reason