Refusing go give money back

My husband bought me a R2000 gift card from sunglass Hut for Christmas. I found 2 pairs I liked, but I don't want shelf stock. So i cannot find anything I like. So now we try to get refund, they refusing to give my husband his money back. Unacceptable! Tried calling customer services multiple times, no one answers or calls get dropped when I select refund department. If I do not like anything in your store I should fave the right to get my money back.