Layers turn into pixel noise – background

Hello everyone!

I have a problem. I'm working with a file in Photoshop and saving everything properly. But after some time, when I exit Photoshop and reopen it, my PSD file no longer contains layers—instead, I see a pixelated, locked background.

I'm using the latest version of Photoshop (I had the same issue in the previous version as well). I always save my files correctly, and the "Save as Layers" option is checked. I've been using Photoshop for 10 years, and this is the first time I've encountered this issue.

This happens randomly with certain files when I try to open them, and they cannot be restored.

Does anyone know what could be causing this?
How can I prevent this issue from happening with other files?