Copy of receipt and clubcard dont qualify for cash refund

Clicks at columbine square are refusing to give me a cash refund with my original slip even though I have a copy of my slip and I paid with my club card so the 3 day old purchase is formally recorded. I'm disgusted at being offered a gift voucher. I bought the goods on Thursday and today, Sunday, they telling me I cant get cash back because I've disregarded the receipt. What's the point of the membership card and having a copy of my receipt. Regards Melita *** *** .