Ghost Touch Problem

I am facing ghost touch issue on my iphone xs since last three months. apparently it looked like a software glitch but it turned out to be a hardware issue. And strange thing about this issue is, it only behaves insanely (like typing, opening camera, clicking photos, opening messages by itself etc) when it catches 2G signals. It works perfectly fine when on wifi or 3G or LTE cellular signals. only creates problem when someone is calling and 3g or 4g signals are low and it converts to 2G signals. Need expert opinion, what could be the reason of that. Thanks