Mall@Carnival Foschini bad customer service

I bought 2 bags online at Foschini on promo, but then decided to return for exchange because they were the same, I asked a cashier lady there if it was possible to return then she said yes, she went through with the process but told me at the end that it's not possible they have to refund me. I asked her how was it possible she gave me so many reasons ending up calling the supervisor, same with her she even gave me attitude. Why didn't they explain before we went through the process of exchanging only to refund me? Their customer service is so bad and I loved the bag and asked if I can stay with that one still they said I have to get refunded or buy with normal price. Foschini at carnival mall is bad with customer service.