Ignorance and bad customer service

Today i went to Truworths Circus Triangle in Mthatha to exchange shoes that i bought there recently. I wore the shoe once but i was forced to take them off me at an event i was attending as the other side was so uncomfortable. It caused me to walk abnormal as it feels like it about to break. So they could not help me because the shoe was worn as they have to “put it back in store for another customer to buy it” as if it won’t experience the same problem as well. I was also told by the manager that they would have taken it back if it was physically damaged, so i don’t know whether they are telling me to actually break the shoe myself in order for them to know that it is not in a condition to be sold to customers.