Why is my iPhone X touch screen hyper-sensitive?

I'm using iPhone X, which is acting completely strange. When I use in hot weather (or room temperature), the touch works fine, but when I'm in air-conditioned room, the touch becomes oversensitive (or hyper-sensitive), especially the lower half of screen. This is highly irritating when typing a message through a keyboard, touching one key, adds extra 3-4 characters. It even responds to false touches when I have just placed fingertip just close to the screen (not touching the screen).

I've been using Original Apple Adapter, I have tried almost every method available on this community, like hard-resetting, power-off for 30 mins, removed the screen protectors, disabled 3d touch etc, even tried adjusting sensitivity with 3D touch on, nothing seems to work. The only thing that I didn't try is factory-resetting.

[Re-Titled by Moderator]

This behaviour started out of nowhere. It didn't fell, it never fell into water or exposed to water etc. This isn't also dependent on power condition whether the battery is low or fully charged or working on 'battery saving mode' or even plugged-in. It's just doesn't work in cold environment but works fine in hot or normal environment. Please guide what should I do?