Paytm — voucher I bought is not useful and not refunding money

Address:

Hyderabad, Telangana, 500072

Hi team, I bought brand factory voucher of 4000 rs on 14 Dec to use it in sale. But Kukatpally brand factory store not accepted the voucher so I bought all the things with credit card. And the voucher is not useful for me.
I have raised the compliant same day and asked to cancel the order. In T&C it says it will accept in all brand factory stores. But they didn't accepted it. Due to which my 4000 money is locked in voucher which is not useful for me.
They are saying it is not refundable. How can they say that when the company not able to use it. I have updated all details in ticket but they closed it now. I need help in solving it and getting my money back.