Not receiving a refund but rather store credit when I wasn't given what was promised. (Store credit will not be used)

About three weeks ago I placed a deposit for a lay-by of R500. The product was promised to me with two lenses, but settled for one lens, at R6999. Last week Friday I made another payment of R800 only to see a balance of R6699 when I've already paid R1300. They pitched a different camera with two lenses at R7500 but when i asked them for a refund they told me that they can only do store credit and to be honest, I would rather like the refund. I did not receive what was promised to me and was left disappointed. Now Fuji Film Image centre in Kenilworth Centre is sitting with R1300 of my money and I received nothing. I basically paid for nothing at all