TAPE Store in Pretoria Central

I bought Diesel sneakers around January, lost the slip but I still have the proof of payment as I bought them via eft. I wore them only once and the Rubber that goes round o bout the shoe started tearing off. I sent them back to the store for an exchange as I only wore those shoes once. I was so embarrassed as the store assistants were shouting at me and I was trying get my best to be civil with them them. They ended u telling me that they need the slip and they won't help me without the slip bit I told them that I have the proof of purchase which is what they wanted but the flatly refused to assist. I even asked them that what is it that I must do with these shoes s I can't wear them in the state that they are in. One assistant even said "what must I do with them as they have already been worn, I can't sell them because you have worn them"