See if this helps:
1. Go to settings/music on your device and make sure you are signed out of 'iCloud Music Library’ and 'Apple Music'
2. Go to settings/iTunes & App Store and make sure you are signed out of your appleID.
3. Go to the music app on your device and open your profile (icon in top left hand corner of screen) and make sure you are signed out there too.
4. next go to your PC and open up iTunes and go onto the general tab in preferences and make sure the check box to use iCloud is ticked ... You may want to untick it and apply the settings and tick it again and reapply the setting, if it was set already.
This works best if you are an iTunes Match subscriber as it will also share any music you have purchased elsewhere or 'ripped' from CD and have matched to the iTunes Store or have uploaded to your iCloud.
next go back to your device...
5. Go to settings/iTunes & App Store and sign into your appleID.
6. Go to settings/music on your device and check you have both the 'iCloud Music Library’ and 'Apple Music' switched on ... If not turn them both on.
7. Now go back to settings/iTunes & App Store (this is important) and make sure automatic downloads are turned on for music/apps/books etc. also turn on the 'use mobile data' setting too, if you want to stream/download music over your cellular network.
Now open up your music app on your device and make sure you are definitely signed into your profile
When looking in 'My Music' in the Apple Music App, either at the top of the screen (iPad) or about half way down the screen (iPhone) there is a menu with items such as Artists, Albums, All Playlists etc. tap on this and use 'Show Music Available' Offline to control what you want to see listed on your display.
Now see if the app works correctly for you without crashing.