Unable to access Apple Music family plan on son's Android phone

I have the family plan and my son is not able to log in today for some reason. He was logged out and it's now saying that he doesn't have an Apple ID. But on my account it says he is still on there. I tried deleting him from my account, but it will not delete him so I can send him another invite. He tried to change his PW, but all it says is that it's now locked from too many attempts.

[Re-Titled by Moderator]