Groupon India / Nearbuy — big bazaar gift voucher

Address: New Delhi, Delhi, 110092

Hello,
This company is committing fraud by selling invalid Big Bazaar gift vouchers.
I bought a Rs 500 worth voucher from them on 17-Jan-2019 which was supposed to be valid until 08-Aug-2019.
But when I tried to use it at Big Bazaar on 01-Jun-2019, I was told by Big Bazaar that it’s invalid.
I saw their screen at checkout counter and they were right. It was coming up as invalid.
Since I bought it at Nearbuy, I complained to them but their answer is that they cannot check if vouchers are valid or invalid. So, they cannot do anything.
Is this kind of fraudulent business practice allowed in India ?
If not, I request Consumer Court to help me by getting either a valid voucher from Nearbuy or the refund.
I’d also urge Consumer Court to take strict action against Nearbuy since they seem to be employing such fraudulent business practices.
Thanks