Paytm — I have not received a cash back

Address:	South West Delhi, Delhi, 110075
Website:	paytm

I booked a bus ticket from paytm with order number- [protected] and applied the promocode FLAT140 for rs 140 cash back but i have not received any cash back and i submit a complaint as well with ticket number[protected].but they are reverting me with a message that" i have not applied any promocode" which is totally lying.. because this is not possible as i booked the three tickets continously and i got cash back for 2 tickets but not received the cash back of last ticket . and i also want to add one more thing that even they dont reply on my mail . MY contact number-[protected] my email [protected]@gmail.com