In addition, I found that when the setting of Frictional is changed to "Adjust to touch" from the default "Add Offset, No Ramping", both the Equivalent Stress and Total Deformation dropped. (Yes I can now run the simulation with frictional somehow, guess its because I strengthened connections in other places. Anyway.)

Can you tell me under what conditions "Adjust to touch" should be turned on or off? Should it be On when the default "Add Offset, No Ramping" already runs simulations without error?