No refund on faulty item.

Hi, I purchased a R279-00 wooden toilet seat from your Rosebank store on Friday the 21st June. 3 days later it broke. I took it in to your Cresta store and was told that they can refund me a voucher because I had no receipt. That was fine. The sales assistant then punched in a code and told me the refund amount will be R229 as that is the selling price now. I said that would be unacceptable. The manager was called who then told me I couldn't have bought the item at that price last Friday despite me showing her the bank sms notification and the item is actually 99 cents but there is no stock. I once again said that this was unacceptable, the manager said there was nothing she could do as this is your policy and I must go to Rosebank to see what they say. I can understand if I just changed my mind and no longer wanted the item but the fact that your product broke means that I'm entitled to a full refund. This policy must be in breach of the CPA and needs to amended.