Reliance Trends — regarding credit note

I had made the purchase in the month of nov, 2017 and then due to some reason i had to exchange the product. I was given credit note which was in the form of card for the amount of rs 1299. The expiry date mentioned was 23/03/2018. On 21st of mar, 2018, when i walked into the reliance store gip, noida, the staff informed me there is no balance in the card. Which was very disgusting. They told me you need to raise complaint to the same store. But still no one listened to me.