How do I recover playlists of purchased music after re-downloading the Music app on iPhone?

I recently accidentally deleted and then re-downloaded my Music app. Now, all of my playlists are empty - I do not have, nor have ever had, a subscription. I’m just talking about my playlists of purchased music. The named playlists are all still there, the songs have all just disappeared. There’s no option to sync library with the cloud that I can find. Am I missing something? Are all of my playlists just gone now, or is this some sort of glitch?

[Re-Titled by Moderator]