When you sign into your account on another device, it should show the music that you have saved to your Spotify account (playlists, songs, artists) You can then download those songs or playlists for offline use if you want to.
If you still have trouble seeing the music on your other devices,
I suggest you contact support so they can take a look at your account and help you
If you get an automated reply email telling you to check the help section or the community, you need to reply back to it.
Support usually replies within 24-48 hours.
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