I can't sign in iMessage and Facetime with my Apple ID
I can't sign in iMessage and Facetime with my Apple ID. It says in iMessage "an error occured during authentication.", and in Facetime "This account has no reachable addresses.Please sign in to appleid.apple.com in order to add one." What am I going to do?
[Re-Titled by Moderator]
MacBook Air 13", macOS 10.15