Worst exchange service ever

Worst service ever. Yesterday I went to Foschini in Menlyn Mall, to exchange a pair of jeans (Which I had previously bought with my cheque card) with sunglasses. I got the sunglasses then went to the till to do the exchange, instead of doing the exchange Eva the cashier did a return and transferred the money back into my bank account, which by the way is not reflect into my account. I asked what was she expecting me to pay with now that she did a return instead of an exchange, she basically told me she doesn't know I could always go to another Foschini to buy those sunglasses. I had plans with the money I had with me, hence I wanted an exchange not a return, and since that was the last pair of sunglasses that i wanted, I was forced to pay them with my money that I had other plans for. I am not impressed and I am not happy with the service, if she didn't want to assist me she should have not done it.