Layers in Composition empty

[Danny25790231di5g]

I have to build several small lottie animations (20) which I arranged in folders in one big file. I'm working on this file since weeks. When I went back to check other animations, I realized that the animations were gone, there were no files in the comps anymore. I did not forget to save or another mistake as there are several comps missing layers & animations. 

I deleted disk cache (although my machine has 36GB RAM) I also installed the latest version 24.3.0. Is there maybe a setting which isn't correct. Is there a bug I'm not aware of? 
Any help / suggestion is welcome, thanks.

[ShiveringCactus]

I've not seen that before.  Typically if a file disappears there would be a placeholder highlighting that.  Is there any chance you've run one of the clean up options in File>Dependencies or deleted a solid that was used in all the animations?

Are you using any sort of cloud back up?  It might be that an older version is available that still has the animations.

[Danny25790231di5g]

Thank you for your reply.
No, I just deleted the disk cache after I recognized that the animations were incomplete.

I save my work mostly on my internal hard drive.

I assume I have to re-build the animations from scratch. I was just wondering if this behavior can happen if you take action xy