Dear friends, this is the info about cameras repaired in 2023.
Some cameras got the new curtains made using Japan-made curtains material. I have 3 kinds of material and one was show the problem. Problem is the lost adhesion to the rubber-based glue I used for a long time. Looks like the rubber on the silk material is not exact rubber, but something else.

I do not know exactly in which cameras I used that material. But if your camera stop working suddenly or you can see partially detached curtain  - do not worry please. I'll fix your camera again as a warranty repair. Sorry for this issue!