Dark spots on mesh

Hi, I am hopefully posting this in the right section. I am quite new to working with UE4, and have stumbled over a problem all my googeling has not managed to solve. Hopefully someone here can help me out.

I am getting some dark spots on my meshes, that does not disapear when putting on materials.

I have tried importing both fbx and .obj files, with same result.

Engine 4.25.4