I have some albams we have purchased but some of the songs are saying the computer is not authorized to play this song I enter my user name and password but still get the same message.

If the message to authorise songs keeps re-occurring with the same songs, that suggests that the song did not download correctly; i.e. that the file is incomplete or faulty. In this event, delete the song and download it again from the iTunes Store.

I also have the question. But some of the songs are ones that I uploaded into iTunes from CDs on my previous MacBook Pro. Now I have a new MacBook Pro M1 without a cd slot/player. The weird thing is that some of the songs are still on my iPhone, but not my iPad. When I check sync all songs in Library they don't come over and although I authorized them several times they don't play on the MacBook and aren't on the iPad - although I do have them on the iPhone. This is incredibly frustrating and I would really like to enjoy my old music on all of my devices. Please advise. Thanks.

Thank you for the answer. I received the same message and tried your suggestion. It worked perfectly. :)