some local files won't sync

[c0zm1c]

Plan

Premium

Country

US 

Device

iPhone xs Max

Operating System

iOS 12

My Question or Issue

I have 9 mp3 files that are all part of same album I purchased. When I add them to my playlist from the desktop app (Mac) they all show up there and play fine but only 3 of them sync to my iPhone. I have tried everything... and consistantly the same 3 songs get synced. I checked the tags and all 9 of them and they have identical tags. I have tried different WiFi, rebooting the phone and laptop, deleting the playlist, creating a separate playlist and etc... Nothing has worked. 

This worked a month ago and now as I had to get a new phone doesn't work any more.

PLEASE HELP.....