iMovie Project Corrupted, Cannot find Backups

Hello everyone!

I have been working on a video in iMovie for a while, and have put a lot of work into it. It is saved in a library on an external drive. Recently, it seems the whole project got corrupted, and all the work I had done was gone.

(It says "0s", but before I had over an hour and a half of footage)

I found the backup folder for iMovie, and opened the last saved library, and it was fixed! But then it happened again. And this time, I can't find the backups folder! I've tried all the different file paths, but it almost seems like it got deleted, which I'm pretty sure I didn't do... Will I just have to restart the project entirely?

Thank you!