Bad customer service

Bad customer service, not being able to exchange a size for a present that my son received. I was told to inform the person to return them as they want to know of they must put the money back in the account or not? I stated it was a present and I don't need the money just needed to change the sizes.I would have understood if I wanted money back, why are we able to it at other stores but Truworths is trying to be difficult? This is some of the reason why I closed my account bcs whenever I bought something for someone it was difficult to exchange the items with their tags on.