What part of the constitution are in conflict in this standoff. Between Donald trump and congress

Impeachment inquiry is the conflict between Donald trump and congress.

Explanation:

There is a war going on right now between the President of the United States Donald Trump and the congress of the United states and the war is regarding the impeachment (which means that there has been a misconduct in the power of the office holder) inquiry.

The white house said that it will not co operate with the president and accused the resident that he was breaking the oath that he took in the office and also questioning the elections of the United States.