New purchases from itunes and older purchases and other music that plays on my PC in itunes won't sync or play on iphone
I have 1,000s of songs that itunes plays on my PC and everything used to sync and play on my iphones (for over a decade). Now 20% of the songs don't synch anymore. Sometimes it's (1) the song just doesn't copy or copies and disappears, (2) the song appears to copy but is greyed out once clicked on it, (3) the song says not available in region, (4) the song plays once and then doesn't anymore. I've read all the posts and suggestions on this and it's 100% a Apple music matching issue. And i've noted most recently that some of the grey albums (for example) are matching to the same artist but wrong album both of which are available on itunes - this seems to disable both albums on my iphone (again they play on my PC in itunes). So it's not a region issue at all but a mismatch on the Apple side.
Even when I buy NEW songs on itunes (literally just now today) they play on my pc but won't synch to the phone!
I've tried all the usual stuff people suggest - wiped my iphone clean 3x (complete reset), reloaded itunes and all the music, deleted all the music and reloaded all the music. I've reset the country code. I've logged out, in, out, in probably 20 times. Rebooted the PC, the iphone at least 30 times. I have apple music off, I have the latest drivers... This happens even with a fresh device, and 2 playlists of songs... it's very frustrating. How do I fix this?
iPhone 12 Pro Max