How to STOP unwanted unknown Playlists populating in Music on Mac

I seem for some reason to be plagued with unwanted and unknown Playlists each with unhelpful 'names' (such as 0-5SBNB4VSELOQDBNOH7VJZT6XGHLCHU33-1195723) appearing repeatedly in Music on Mac.

I have, so many times, laboriously deleted each from my Library one after another, then unsyc'd music, removed the app, reloaded the Music app and hey presto all the annoying playlists are back.

I haven't created them, nor have i asked to have anyone else's shared with me.

How on earth do they keep appearing - an more importantly how do I stop them appearing over and over again?

for example....