Bad customer service

I am very upset and disappointed with the service I got from this store. I bought some winter stuff for my kids and was at till and saw when teller scanned the 1onezy I saw the amount was more than in which railing it hung so I asked if I can exchange it for the cheaper 1 I was told that she was going to ask her manager who was standing there and she blindly said no without being given a valid reason and I ask can I than leave it. She informed me that it's not possible. I heard one teller mumbling about it being closing time and that was most probably the reason why they didn't want to. I spend the little money that I had on needed clothing and could've saved but not only that the lack of customer care for me was upsetting. I will surely never set foot there.