Forced to buy goods with my refund

I bought a 10m cable at Buildit Tubatse (Burgersfort) on the 3rd Feb. My Electrician did not use the cable, and it was still in packaging. We returned it to Buildit on the 4th and sadly they refused to refund us - they forced us to buy something else. I explained to them that I need the money but they still refused to pay me bac****!