u/Disastrous-End4036

Hi I am an intern and was informed to create a From-scratch axisymmetric Hertz model: peak pressure within 2% of analytical, mesh-converged with boundary load, ball on disc model. My model works whenever I have both a boundary load and a prescribed displacement but whenever there is only a load, an error occurs. I want to be able to have only a load and to be able to find the displacement from the applied load (having a free displacement also causes an error). I know there is a way to do this but I am unsure how to. any suggestions?