Opening a project, and audio files are missing/corrupted

Hi all,
This is my first post here, and I’m not a tech whizz or anything like that - I’m going back to some of my projects, hoping to grab the stems to send over to a friend to mix - going back the projects aren’t in the state I left them in - audio files are there but silent/noisey old takes that weren’t in the final saved form of the project are now running all the way through, and I can’t seem to recover them at all. I’m sure I’ve messed up somehow, but want to know how I could avoid this in the future/recover some of the files.

I’m using Cubase Artist 10, and have am using a PC with Windows 10. I can try and find out anymore specs if they’d be useful. I always saved after exproting, and have the exported files so I know how the tracks should sound, and most of what is missing.

Hope I’ve done this right, and that some Cubase magicians might be able to help.