When creating new users, there is no nickname field in on the user profile or in the pure JSON for that user. Thus, when trying to login as this new user, the JWT returned does not have a nickname. Old users that were created just over a month ago or earlier do have the nickname returned in the JWT because it was set at the time of creation. Auth0 used to set this automatically, as there is no option to manually set or edit the nickname in Auth0. We use the nickname in our application but because of that our new users, who don’t have a nickname, cannot log in. Our users are created using an email and password, rather than using a third party.
Correction - the JWT is not part of the issue. The issue is that the JSON on the user’s profile does not have a nickname field
Please refer to this thread: Creating a new user in the dashboard doesn't populate the name from email anymore?
The issue has been corrected now. Thanks for reporting this.