Xiaomi India — Redmi note 3 phone defective product received

Address:	Chennai, Tamil Nadu, 600097
Website:	www.mi.com/in

I had ordered for a redmi note 3 and got a defective piece on delivery. I have reached out to them via email and chat for the last two weeks. There is no definite response. False promises. No call back. The defective piece has not been picked up. I now need a refund. Not sure how to go about the same. Every time a customer service executive has no clue about the after service. They dont know when the defective product will be picked up.