My money is not needed in their store

I went to JetMart Mitchell's Plain to return a pair of shoes. I produced my till slip which was within the 30day period. I was told by the cashier that I can only return items within 7days of purchase. I asked for a manager as I have never heard this before. The cashier returned and said the manager said no no returns after 7days. After standing for 20minuets he eventually came. He said that there is a new policy and edcon is moving ahead with the times. I showed him that at the back of my till slip it shows that I have 30days to return. This is the point when he starting shouting at me and said that he will not return and I don't need to shop at their store if I'm not happy with their procedures. I asked him for a printout of the new 7day policy that only applies to their store. He then shouted back at me saying that my money is not needed in their store as lots of people shops there. I asked if he was the store manager and he said no. I then asked for the store manager which came and said there is no such thing as a 7day policy and they must return my item. When I told him about the manager I just spoke to he rudely said I'm welcome to call the call centre to lodge a complaint