Nearbuy — domino's coupon not purchased but debited my paytm account

Address:

19 shubhkamna society (1st floor), B/H kanak-kala flats, Opp Kanchanbhumi flats, Anandnagar 100ft road, Satellite, Ahmedabad, Gujarat, 380015

I got a message from nearbuy that thank you for purchasing the dominos coupon worth 500 and 300 and amount also got debited from my paytm account. I have not purchased any coupon and still due to some fault in nearbuy server this thing has happened. They are now denying to refund my money back. This is a true cyber crime done by them where they debit the paytm amount from customer and auto purchase the coupon for their sales.