Paytm Mobile Solutions — does not refund my money.

Address:

Gautam Buddh Nagar, Uttar Pradesh

Madam/Sir
I place an order on 13th August 2017 on Paytm app of iKall tablet of Rs 5749 and paid through online. I read a various negative review of the same product on different shopping portals so I decided to cancel the order. I cancelled the order on the same day, i.e., 13th August 2017.
The seller did not ship the product. There is a policy in paytm that if I cancel the product before the item is being shipped then I can get my money back immediately. But I did not get my money back.
After 24 hours I do not get any response from paytm.
I tried to call them but unable to speak to the customer executive and they put me on hold eveytime.
I aslo write a complain regarding the same subject but they close my complain without giving any response.
I request you to help me in this regard!