Possible hack??

Yes, if you did not play it then change your information.

Do you have any siblings with the ability to play on your xbox?

If so, confront then about it.

Also check to see if your other game history changes.

If you feel that your account has been compromised, it's best to call support and have them open an unauthorized access case.

You should also never give your account information to anyone. Even a friend. Your account is your responsibility at all times, so even if he were to do something just as a joke or to mess with you, it could wind up getting your account banned.

have you spoke to microsoftsupport? and have you had your xbox off for some time?

I've never seen anything like that. As long as you changed your password you should be okay. I wouldn't try support at this time as they are most likely backed up right now.

Switched my xbox on today to see this message pop up on my sign in screen. I backed out to the main dashboard and attempted a sign in and the message was no longer there. I decided a hard reset and changed my password but I'm curious so hear what
it could be and if anyone else has seen this.

Might want to also check for other accounts that might not be yours on your xbox