Zero or negative pivot error in Franc 2D

Does anybody have some expertise on Franc 2D?

I have a 2D plate with different material regions defined on it. When I try to run it, it says Zero or negative pivot. Check for Rigid body modes. However, when I perform the same analysis on the plate with the same material all through, it gives me perfect results. Im performing the simulation on Franc 2D. Could someone tell me what I could be doing wrong?

I dont have experience with Franc 2D 🙁

-Jorgen