Game Center log-in error

I'm running iOS 9.2.1 on a iPad mini. Trying to log in a child's account into the Game Center. After I agree to the EULA, I get the following message, "Your request could not be completed due to an internal server error. Please try again in a few minutes."

I've reset the password on the account and can log into the iCloud account on my Mac Mini (OS 10.11.2). I don't want to lose the Game Center info for this account. Any ideas or suggestions would be great.

Thanks