Xiaomi Redmi — service and warranty issue

Address:	Mumbai City, Maharashtra, 400055
Website:	www.mi.com/in

Hi Support,
I have Redmi note 4 64 GB phone. and from last 15 days. I am facing an overheating issue. and I have visited TVS electronic Malad West Mumbai.
but I am shocked by your service center reply. the told me your PCB issue and your repair phone from outside. and I haven't given my phone to any unauthorized person. and one common thing. if my phone is under warranty why repair from outside and pay money to outside person. and I understand warranty policy.
I am 100% sure this service center mistake. so please investigate and resolve the issue ASAP. if you need any more details please let me know.
I have attached my worksheet and invoice.

Name:- Sushil Mishra
date of purchase:- 22 Jan 2018
model:- Redmi Note 4 64 GB