Apple Music tracks keep disappearing

Hello.

I've been having a problem with Apple Music for awhile: whenever I buy a digital album or specially, whenever I transfer music from a CD to Apple Music, there's always some tracks that eventually disappear.

By 'disappear' what I mean is, they simply are 'deleted' from my Apple Music Library. But they're not deleted by me! Can anyone explain me why does this keep happening? What can I do to avoid this situation?

(Just in case it is important, I'm on a MacBook Pro M3 Max).

Thanks for any help/suggestions that you may give me.