Make sure iPhone has Touch IC problem

I have an older iPhone 6. The frame of the phone has been bent and touch function sometimes works. I am not sure if it is a Touch IC problem as there is no grey bar at the top of the screen. The display does not flicker and it is just the touch that stops working. Also, whenever I apply pressure to the touch ic area, the touch starts glitching out. I have tried 2 working screens on it with the same result. I just want to make sure that it is a touch ic problem. Any thoughts?