Apple Music stops playing on its own

I'm pretty new to Apple Music. I’m using a iPhone 15 Pro Max with iOS 18.0.1. I’ll turn on a playlist and it will play a few songs and then stop on its own. If I leave it it will sometimes resume playing on its own after several minutes. Other times it won’t continue playing at all. This is not an occasional occurrence, it happens every day. Super annoying! It seems to work fine when I’m on my phone but not when it’s locked. Any idea why this keeps happening? I was recently using Spotify for years and I never had this problem.