Broken goods

I purchased a PC game 2 weeks ago. The game did not work. Disc 1 wold not read, I could not install it.<br> I returned it to the shop and the manager told me it was my PC, not the disc that was the problem.<br> I was then given a gift card, not cash but a gift card forcing me to spend my money by CNA.<br> <br> I went back on Saturday to see if they had another copy, but to my surprize, they had put the broken game back on the shelf. Someone else will buy this game and also be forced to accept a gift card.<br> <br> Why cant I have my money back? This is also not the first time this has happened.<br> I pay in cash for working goods, if they do not work, I want my money back, not a gift card.