FidanJ.42801 (Customer) asked a question.
New users can not login after first login.
A few days ago we started having this issue where newly created users would be signed in the first time their account is created but after they logout, the next time they try to log in, they get the error "Unable to sign in" and the logs show it as a VERIFICATION_ERROR. As you can see in the image below, the Actor ID field is shown as unknown. The other (existing) users have no issues logging in, it only happens for newly created users.
Sounds like an attribute mapping issue
Seems like you're right, when I try to login with the username, it is successful, but the issue still remains that the old users have no issues logging in with their email while the new users are only able to login with username and nothing was changed on our side. It just started happening.