Defining contact in Geostatic step in ABAQUS

Hello,

I have modelled a geostatic step in an undrained clay in ABAQUS. This step finishes very quickly and correctly. But the geostatic step is not converging when I have a circular steel plate inside the soil mass (tangential behaviour is through coulomb friction and normal behaviour is hard). Does any body know the reason behind this divergence? 

Regards,

Cyrus