When meshing a thin sheet. The mesh shows as a non 3d mesh with no thickness replacing the element. Once Test is run - Von Mises can't be selected in these regions, because they don't exist. No Errors occurred.
I am not too sure if you're asking a question, but I am assuming you're wondering why your mesh is not a 3D mesh.
If you're using the sheet metal function to create the part above, most likely the mesh type used for this simulation is shell mesh, which is a 2D mesh. You can revert it back to 3D mesh by changing it back to solid mesh.