Hi,
I was creating an animation in Krita yesterday, and when I came back today the files were corrupted.
This keeps constantly happening when I save an animation file, and there seems to be no way of fixing it to me.
If anyone can help that would be great.

How big are the animation .kra files and how big/complex are the animatioms themselves?

The only time this has happened to me was with some animations that were 400MB, 150MB in size and I believe this was due to me using a very old SSD that I've now replaced and had no further problems with. Fortunately, I make archive-backup-copies onto an external drive and was able to recover the originals from there. Is your drive newish and otherwise reliable?