If you’re seeing that banner it would indicate the user is registered with social auth, e.g. Google or Github so the password is not maintained on our end. Have they tried logging in with one of those methods?
If they are registered with E-Mail/Password authentication, once they incorrect password is entered the Forgot Password flow will appear on the form.
If they’re still blocked - can you please submit a ticket to support@langchain.dev with their E-Mail address? If they were running into any specific issues or errors trying to log in please include those as well.