How do I get my music library back? Had to re-enter Apple Music info, once I did my entire library was gone.

Every few months I’m having to re-enter my info for Apple Music subscription. This last time I did so and all my music was gone. It loaded a random list of songs, and none of my playlists were there. I followed the steps of going into settings, selecting music, and clicking on I cloud music. That did not work. How can I get all of my music back?