Apple India — Iphone 6 32Gb S.G / MQ3D2HN/A [protected]

Website: www.apple.com/in

I have purchase my new iPhone 6 on 28th April 2017 and on the 10th day I came to notice that the device can't do a proper Video chatting. So the very next day I dropped the device to the nearest iCare - Ample at Edappaly, Cochin, Kerala and waited for the 2days [48 hours] and by them they have updated me that it need a full diagnostic check up and require 3 more days. But now they are telling it requires 7 more days.
How could a customer purchased a new phone and waits fro it to get repaired.

How can I get it replaced at the earliest