Hi @robin4862, thanks for posting on the forum and welcome to the SimScale Community 
It’s hard to tell what the problem actually is without having access to your project in particular (take a look here to learn more about our sharing options).
However, keep in mind that Static simulations need to be constrained for them to work. This means that, for any force that’s being applied, there needs to exist a boundary condition which resricts all of the bodies (in every direction).
Our users tend to find our introductory tutorials helpful in understanding this concept! Let us know if you do too:
Cheers
Igor