Paytm — Cashback and voucher

Address:	Mumbai City, Maharashtra, 400078
Website:	www.paytm.cpm

I received a message from paytm to add Rs1000 in paytm wallet and avail instant cashback of Rs 50. I did the same but didnt receive cashback. Also along with that i was assured a Gift voucher which i used after four days of receipt of the voucher and i got a message that voucher is expired. I also explained my grievances but i am not getting the solution.They are every time asking same question, need help in resolving the issue