TERRIBLE EXPERIENCE WITH GADGET CANDY HAYFIELDS PIETERMARITZBURG

I entered into a layby agreement with Gadget Candy Hayfields, Pietermaritzburg. Due to financial reason I was unable to pay the outstanding amount, I requested the store manager to allow me to take something else which would be inline with the amount of money I had already paid, he did not want me to exchange nor does he want me to cancel the agreement, instead he told me its the law and that if I do not pay the outstanding balance by end of June I will forfeit the R4500 I have already paid. Needless to say he was very rude when I tried to engage him on the matter. I have written to him regarding my rights as a consumer but I have received no response. This is the worst company I have come across, they have no regard for customer service, and it is clear that they have total disregard for consumer rights .