Unable to login to keycloak that's been integrated with AD with LOGIN_ERROR clientId=null messages

Hi

I am unable to login to Keycloak that’s been integrated with ADDS. The test connection and authentication have been confirmed working. I could fetch all users from active directory to keycloak. The issue is when I try to login using those users (user1, user2, user3 etc), I am unable to login and the login windows keeps shown and I also get the below error message as well.

Any help is appreciated.

[org.keycloak.events] (default task-51) type=LOGIN_ERROR, realmId=3247c2af-981c-4ad5-a690-f5a3e8517e51, clientId=account-console, userId=null, ipAddress=0:0:0:0:0:0:0:1, error=invalid_user_credentials, reason=‘illegal negotiate token’, auth_method=openid-connect, auth_type=code, response_type=code, redirect_uri=https://localhost/auth/realms/TestWare/account/#/security/signingin, code_id=653a233e-2e8e-4c43-84cb-807ffbe4ecb3, response_mode=fragment, authSessionParentId=653a233e-2e8e-4c43-84cb-807ffbe4ecb3, authSessionTabId=bJ1wW6IuKdQ

This is a strange error message, do you have some custom code on your keycloak, something that might generate this error message?

No particular custom code, except the keycloak is integrated as part of another application.