Music won't properly sync its iOS and macOS data.

I have a smart playlist created on my Mac that is synced to my iPhone. The list is comprised of songs that are locally stored on both my iPhone and on my Mac. I have primarily been using my iPhone to play the list.

The list depends on the "last played" field. Each time a song is played, it's new last played field no longer fits the list's parameters and the song vanishes from the list. As a byproduct of this I can easily tell if a song has been played since I started playing the list. There a little more than 11K songs on the list when it begins to play.

When the list completes playing on the iPhone—when it has no more songs—I sync the phone with my laptop using a lightning cable. But after doing this, not all of the songs have their date fields updated. Anywhere from 20-200 songs won't be marked as played on the Mac when they most certainly were played on the iPhone. I have to play each song in masOS's Music to get the app to mark the songs as played.

I would (perhaps obviously) like things to work as they ought to work and would appreciate any advice that might help me fix this problem.

I use an iPhone 11 running 16.5 and a 14" MBP M1 running 13.4.