Paytm — My return is rejected

Address: Gautam Buddh Nagar, Uttar Pradesh

Website: www.paytm.com

I ordered Videocon Octa Core Z55 Dash (Black & Gold) For RS 5650 on April 6th but got a White phone.It was not as per the specification, apart from that the main reason for return was that the phone also seemed to be used and there are a number of message and calls on 22, 23, 24 of february .from the messages on the phone i understand that it is a returned product from flipkart.

Even though they are required to sell 100% new product then send me a used phone and I returned it via bluedart as they told they have no pickup services here. Even though Paytm would refund only Rs 200. As there were no other options I sent it for Rs 400. Bearing a 200Rs loss.I send them the courier reciept and the photographs of the phone as a proof.And after a few days the shipment was delivered and it was signed by them as per the tracking information. But after a few days Paytm rejected my return without any reason and they accepted that phone.I have send them a no of messages and I have the required proofs.
The seller was crazzykart and now I am at a loss of 6050 Rs without a phone . I dont know what to do. When I send them Email google says that the Email was rejected.
I had the worst experience from paytm
What should I do??