Why does Apple Music Randomly delete my music

I have an iTunes/Music collection I have built up over many years and many Mac products, from my original G4 MacPro, through Mac minis and now my M1Max Mac Studio. I also own an iPad and an iPhone 13Pro. My music files have always existed on dedicated external drive directly connected to my Mac Desktop system, that ONLY contains my music, and I ripped the files to lossless ALAC files from my large collection of CDs. But it seems if I don't play the files very often, the Apple software drops the links and I am unable to play the songs over WiFi using the Apple Remote software. I have to go to my office and log into my mac Studio and click through all the files that have gotten "dropped" or they cannot be played. The missing files have an exclamation Point and if I click them in AppleMusic/iTunes it restores the link so I can select it to play them via my iPhone. I have an exclusive Apple system - there is no windows gear in our home. I don't want to have to dump all of this to get a system that can store my music library reliably - I don't want to play every song tonight, but if I decide to play something a few months from now, I should not have to reload it all over again for it to work. My phone is NOT set to Optimize storage - I have a 2TB music drive connected to my desktop and I would expect once loaded that the files would remain there and not be removed by some rule that I know nothing about. How can I get this to work reliably? I'm running Sonoma 14.5