Bad service

My name is JoAnn I purchased my son a pair of Reebok classic takkies at totalsports promenade in Mitchell's plain in December 2018 which I payed cash was priced at 900 rand .Today I wanted to return the takkies for a other pair or something else cause the takkies was defective some of the stichting came loose as I explained to the manager which later told me his name is Clint I asked for his surname he refused to give to me he told me he cannot help me with the exchange cause I didn't have the box of the takkies I told him I don't have the box anymore I threw it away but I have the slip of the purchase and the takkies I even showed him the problem with the takkies still he refused to help me.I asked him for head office number he gave me the number for the helpline .I took it and left.What kinda customer service do they have telling me they can't help me cause I don't have the box of the takkies I spent all that money now they tel me they can't help me they must get the box also.I mean they can't tel me they don't have a extra box in the storeroom or give me the other takkies and keep the box.I was so upset and disgusted by these people turning me away from the store for a box . Someone from that store should call me asap to sort out this problem cause I won't leave this problem like this I will take it even further .