Hi @nivurek, thanks for posting on the forum and welcome to the SimScale Community 
It’s a bit difficult to learn what the problem is without having access to the project - if you share it with support and paste the URL here, we from the Support group at SimScale will be able to access it.
I’ve found an article that might be interesting and provides some alternatives on what might be happening:
Let us know if it helps!
Cheers
Igor