Deleting and reinstalling the Music app can make your library appear empty, but your playlists may still be recoverable. Before recreating any playlists or changing sync settings, check whether your original library is still available.
- Open Settings -> Apps -> Music and make sure Sync Library is turned on, if you have an Apple Music or iTunes Match subscription.
- Check your library at Apple Music on the web using the same Apple Account. If your playlists are there, they may simply need time to sync back to your phone.
- If they’re missing online too, check another device where you previously used Music before making further changes.
Don’t turn Sync Library off and on again yet, as that can remove downloaded music from your phone.
More info: If songs are missing from your music library.
If the playlists are missing from both your phone and the web, recovery depends on whether you have another copy of the library or a device where they still appear.