Curated playlist of ripped CD tracks, not Apple Music, vanished

I spent over a month assembling an 8+ hour playlist for an upcoming event, ripping from physical CDs AND not being delinquent in any Apple Music payments. Today it just...vanished! Off the primary computer connected to my iTunes music library. Other playlists survived but not this one that I built so carefully. This has happened before and I make PDF lists of the songs to reassemble manually, but come on, Apple. It's 2024. You can't let me keep my playlist that I built by hand, over hours and hours and hours? HOW CAN I GET IT BACK? Surely there is a piece of data that matches them together in a playlist just like it matches songs in an album folder. Where/how?