Losing all my collections (again!)

I have lost all my collections again. First it happened when I logged in I restored a backup, which was missing a lot. Then I rebuild some collections but now again they are all gone while still logged in. I can import a backup but it’s not the latest version.

Why does this keep happening, while so many people experience the same for a long time now?

I like the tool but if I cannot rely on my work being saved it is useless.