Myntra.com — Used gift card given by paytm

I purchased myntra gift card of 2000rs from paytm at that time offer is not there that why i does nt redeemed it with myntra because its have validity of 1 year that why i does nt redeem but today while i shopping i seen good item with good discounted rate clothes that why i tried to redeem my myntra gift card to redeem which issued by paytm to purchase that clothes, at that time its says its already redeemed what is this? I am shock please refund money