How different are the results? Are you re-meshing each time? Sometimes if you re-mesh you will get a slightly different result ie 0.0281, 0.0285, but if they differ by a lot ie 0.0281, 0.0115, then there is something else happening. Are you changing the coarseness of the mesh between runs?
Are you using a Fixed geometry as Fixture and why do you use a nonlinear calculation?
When you make different calculations with ever smaller meshes you can see that the stress at the in fixing point is not converging.
I think it has something to do with the St venant principle.
Can you send some screenshots so we can have a better idea what the problem is