Manual Music sync NO LONGER working

OS 15.7.2

iOS 26.1

I have recently cancelled my Apple Music subscription, and now my music library (i.e. all music files stored locally on my computer) no longer syncs to my iPhone.

My full music library still shows in Apple Music App, and all songs can be played / accessed there as well, as normal. I can also add local music files to the Library, and they will show up, as normal. Again, music files are all stored locally, not downloaded from Apple Music.

"Manually manage music" option is not working, as is "Sync automatically". WiFi syncing, USB cable, same result. "Sync only checked music" disabled. "Sync library" also disabled since subscription is cancelled.

What could be the issue here?

Thanks