Unable to copy any songs to any playlist in Apple Music on my MacBook Pro

I can't copy any songs to any Playlist in Apple Music. I am using a MacBook Pro with iOS 15.3.2. I have checked my login, checked that Sync is on, updated my iCloud Library but still cannot add a song. I have gone through my entire Library and randomly tried adding songs ... even songs I have already added. All I get is an icon with the number 1 in the lower right corner (cuz I'm trying to add 1 song), but not a single playlist will let me add it.

Help

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