Sign out is not available due to restrictions
I cannot "Sign Out" an AppleID on an IPad Pro (iOS 12.2 16E227). I recently created an AppleID for a child (under 13) to be used on an old IPad mini. I signed into my IPad Pro with the child's AppleID and now I cannot sign out. "Sign out is not available due to restrictions" and "Sign Out" is not selectable. I need MY AppleID back on the IPad Pro. I have tried EVERYTHING, including 'Restore backup.' I have changed all the 'Content and Privacy Restrictions' within the 'Screen Time' Setting menu. Nothing. How do I Sign out a child's AppleID from this IPad Pro so I can use my own AppleID again.
iPad Pro, iOS 12