Files missing and unusable in CC libraries

Since a few days I have a huge problem with my libraries. Every time I change and save an asset, it won't show up in the library. It just dissapears and I only can see the "Adobe-Icon" (screenshot). And it is not available/present in my library-folder (c:/users/.........Myname/.... .... roaming.....). It's gone. 

What I have done so far to solve the (urgent) problem:

- reinstalled the complete software, used cc-cleaner, same problem. 

- Reinstalled the whole computer, same problem. 

- I left the company (cc for teams) and deleted my account. Made a new account, same problem. 

- Used a new (private) license with private account, same problem. 

- I joyned the company again, made a new account, same problem. Of course I took care of the rights in the admin console. 

- Reinstalled the computer again: Same problem. 

- Tried the CC-library-installation-programm, didn't help. 

Finally: 

I made a new account - again - and I left the company. Now I stay private (outside of the company) with a new abo but I don't know if it has to do with an enterprice account or not. The issue is still there. Well... There is nothing more I can do now. I even modified the host-file (and of course I replaced it finally with the old one again). 

My system is Windows 11 Pro, version 23H2. I have administrator rights and Adobe shows up as "allowed" in the firewall settings. 

Maybe I'm doing something wrong all the time? 🙂

Synchronisation works fine, everything else works fine, but I may not change an asset in a library, then it disappears.