Paytm Mobile Solutions — product not delivered | feeling cheated | no response from paytm even after repeated mails and calls

Website:

www.paytm.com

I ordered on 20 sept and the expected delivery date was 30 sept. It was yet not been delivered. I have been writing them the mails, raising query on the app and reaching out to the call center but i am not getting any reply. No replies on my mail and no one at the call center ever picks up. I have already paid for the order and i feel cheated. I have been mailing and writing but they prefer to ignore and their so called call center prefers to not pick at all. I dont know whom to contact to get my money back.