Apple Music "Content not authorized" error
In Settings > Music, is the "iCloud Music Library" toggled on? I would start with checking that first.
If it's already the case, I would recommend signing out and back in with your Apple ID in Settings > iTunes &amp; App Stores.

I'm subscribed to Apple Music, and had a similar issue recently after changing phones. Something wrong with DRM I assume, so authenticating again should be enough to solve it.