Help; Frames all messed up after adding some in the middle of animation

Hey, I’ve just had an issue where I attempted to add a few frames about 1/4 the way through my animation and all the frames after this got mixed up and moved around? None of the images have been changed but each frame’s position on the screen has been moved, plus a lot of them are out of order now, and some have been completely deleted or duplicated. If anyone knows what’s going on here that would be great, but otherwise does anyone know how I can reload an old save file since it autosaved after the issue occurred?

Thanks!

Followed up here: More detail on issue with adding frames messing up subsequent frames