Worst experience at Jet Gateway

We order clothes for our new born online and one of the items size was extreme off. As per Jet returns policy, online purchases can be returned in store so I made a trip to Jet Gateway in Durban. The supervisor refused to process the refund and made me feel like I'm inferior to her. She then called the manager, another lady who spoke down to me. I was told to do the return online and they flat out refused to refund the item. I explained to them that we paid by debit card online and they insisted that I couldn't have as the online facility only accept credit or store accounts apparently. So how did we pay with our debit card? Are we stupid? I feel this was the worst experience and I will never shop at Jet again! I will be letting all my family and friends know about this experience as well!