stores making profit unnecessary on customers loss

I bought a jacket for my brother some time ago,with a value of R799.00 for my brother's matric farewell in Evaton,but when he came home to fit the jacket the shoulders were too small for him as he could not bend on that jacket,so we bought him another jacked with the idea that we will return the jacket as there is no time limit for returns on the slip we got from the shop,on the 22.11.2015 I went to skipper bar in Carletonville to exchange for something other than a jacket,they took the slip and the jacket and told as to look for something else of that value but when we were busy looking there called us and say we must look for something for the price of R450 as the jacket is marked down,and I asked how is that possible,and they will will find out from the people from evaton,they called evaton mall to call them,and the guy by the of kuli called and they told me they cant do anything for me as the price is marked down,and he give me a number to call and I called that lady with the name of maria who understood the situation but said peter must make a decision,we called peter their GM to find out but he told me its our loss and its not his problem,.