Akshay Maniyar
Ansys Employee

Hi kwak dongkyu,

Sorry for the trouble. I have added some images to my previous answer which can help you in understanding the solution I have provided. Also, if you have a small model with less number of contacts, try refining the mesh for the complete model and see if it resolves your issue. The above method is to identify the contact which is creating issues and then modify the mesh controls. 

Thank you,

Akshay Maniyar

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