Automatic touch and bottom navigation not working

[virusshah1997]

I am having this problem since a few month, after the phone fell and got a barely visible crack on left side of screen i assume this problem started


It keeps on touching random places automatically and does not respond to my touches, sometimes locking and unlocking phone fixes the problem.

but the navigation bar are not working at all


I am thinking will installing a custom rom or formatting the phone solve the problem in case it is software issue.