The Cloud Music Library can’t be updated right now. An unknown error occurred (12002).

I want to synchronize my Apple Music account with all of my devices; but on my Mac, I have this error message when I choose "Sync library" option on (and then also, Merge Library opt.) in Music>Settings>General. Right now, I am not able to use my Apple Music account on my Mac.

ps. I have already tried restarting computer etc.

[Edited by Moderator]