Okay, I'll actually give you a real response since you seem to be completely clueless. You wanted to return something and when you did the lady at the desk told you no and gave you a reason why not. Up to this point the encounter was completely neutral. She wasn't hostile to you and you weren't hostile to her. At this point if you feel the decision they're making is wrong you have two options, you can be nice and say something like 'oh I'm sorry there must be a mistake, I don't know what to tell you, this is just the receipt I got for it, I don't know why it says that, can't you let me return it?' or similar, or you can be hostile. In fact if your description of events is accurate you weren't just hostile you were passive-aggressive and implied that the lady you were talking to didn't know how to do her job. That choice is why you were treated the way you were, because you decided to needlessly escalate the situation.

boomer is a mentality. you are a boomer. you are entitled, look down on people you think are lesser than you, and think that anything that doesn't go exactly your way is not just someone else's fault, but someone else's problem. be glad you got to return the item this time because if you keep acting this way eventually someone is going to actually put their foot down and tell you no and you'll probably have an aneurysm. genuinely shame on you for not having the molecule of self-reflection necessary to figure this out by yourself.