MTN lacks ethics

I had bought a Samsung phone charger from MTN Centurion Mall last Thursday. I eventually realized that this charger does not work. I took the charger back to the same store to return it. They tested it and confirmed that it was not working. They then informed me that they need the original packaging. I had my receipt and there is no mention of keeping the original packaging on this receipt. The lady that assisted me including her manager could not help as they insisted on the original packaging which my **** threw away. They were unable to refund me or exchange the charger as it was not returned on the original packaging. This is totally unacceptable and there is no real customer service or care.