iTunes playlists won't sync between both of my Macs

Hey Community, I'm in desperate need of help. I have been to two apple stores, then when they couldnt help they referred me to itunes specialist on the phone. Apple worked with me for about a week and then said they were sending my data to their computer team with videos i took of my screen. I never heard back from them. I will go into detail the best I can. Itunes is my world, and part of my business. I have worked on my playlists since I was 13 and have my whole life there. When they switched from itunes to music a lot happened and it has been a crazy adjustment. Apple was able to save my playlists at least which is imperative to me. I have always had my music and library saved onto an external hard drive. I have recently switched that to a SSD drive for more safety. I have always had two computers and had my itunes on both reading the same playlists. So i recently purchased a new M2 macbook air and a new Mac Studio as my at home desktop. It is very important that my itunes talks to both computers and whatever i do on one computer saves on the other. I have both 7,000 songs purchased from apple and over 30,000 songs copied on my itunes over time from cds etc. I purchased the laptop first for a few months and everything switched over fine. Once I purchased the mac studio I brought both to the apple store so they could help me set up itunes on both. For the first few days it was working great and whatever i did on both computers was saved to one another. After a few days I noticed it wasnt saving,  thats when I brought my computers back to apple twice and then talked to apple on the phone for a week. Obviously we made sure the same library was chosen for both, and made sure both computers were taking the songs out of the same folder. Nothing was working. Then I saw that my hard drive would not eject properly after I opened iTunes (Music). So when i open any other application and try to eject the hard drive it's fine, but whenever I open itunes, then i close itunes the hard drive won't eject. I make sure iTunes is completely shut off, but even if its completely quit, it seems the hard drive won't eject unless I force eject it. So I don't know if that means the music library isn't saving. Then yesterday I noticed that the changes I made on each computer wouldn't even save on its own computer. Once i started moving some things around now itunes won't recognize the music AT ALL. So as of right now, I'm ignoring why both computers aren't saving each other's playlists and I'm trying to figure out this new problem. If I hook up my harddrive on my laptop, let's say, when I press my songs , the exclamation point comes up asking to locate my music. I went back  to make sure my location of the folder is fine and it is, It goes to my hardrive, music and the folder where all my music is. Then i checked a specific song and went into its info, each song is going to the correct folder but the music is NOT playing. The only music playing is obviously my purchased songs. So now i cant use my itunes at all and I'm freaking out. I need my music and playlists. If anyone can help, I'm open to any resolution. Im open to phone calls or anything. Thank you dearly for any help. All the best

-Brad 

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