From the Screen Shot your put in the forum, You defined Shrink fit in assembly,i think so. I could not get you where you have applied Shrink fit and What is the function of the Assembly why you have fixed Bottom. You just explain function of your assembly and Contact conditions. So that its easy to Give solution or work aroun for your problem.Thanks
CSWP-Advance Nonlinear, Dynamic, Motion, CSWS Simulation, CSWP -FEA.
without knowledge of your application, it is difficult to provide input on the correctness of your analysis setup
but changing directions is by choosing the reverse button in the force definition