Chosen Solution
fell down from 3m hiegt and not on.service center told ic shot really it was the problem no crak is there entire body
So from what I can understand the iPhone 6s dropped from 3 metres in height and completely died after that. The issue is caused by something going bad on the logic board. IC meaning a chip or SMD (on board) components which can be one or more has gone faulty. You will need to take the phone to a mobile-phone shop that does board-level repairs. Reputable ones are one that offer a no-fix no-fee policy.