Music library on Apple TV not working correctly

I've been playing my music on my Apple TV for years (native app, not AirPlay) without a problem, but lately something strange has been happening. If I play anything that isn't simply shuffling what's in my library (e.g. playing a radio station), the app doesn't seem to know what's in my library and what isn't. If I like a song and want to add it to my library, it seems to think it's already in my library (it's not) and if I try to add it, it will not work. I will "remove" and then "add" the song, but if I look on my phone, not only will the song not be there, but it looks like the most recent album manipulated in the library is something completely different.

Everything is still working smoothly on other devices.

Has anyone else noticed this weird behavior with the app?