Huge problems, syncing iTunes to OneDrive

I have two computers. Each have different music libraries. Computer number one is synced to OneDrive with iTunes. Computer number two was not synced to iTunes. I wanted to try to preserve what I had on computer too, so I toggle the switch on OneDrive managed storage to save, my music. Now my iTunes library has reverted back to computer number one library. And when I attempt to go to an old iTunes library, it doesn’t have anything I put in from the last two years and none of the files will play. I really need some serious help please. I can’t believe that it’s erased two years worth of work on iTunes. Somebody please help me!