Family Dollar complaint: Declining sales in New location

I walked into my local Family dollar today with my coupons in hand and a smile. That smile was instantly disrupted with the lack of knowledge and ignorance I received from the MANAGER. He scanned all of my items and after he successfully scanned and completed my transaction he decided to double check my coupons. This is not the issue I have. The real issue occurred when he decided to tell me my coupons were fake. When he realized he was wrong he then wanted to know exactly where I got my coupons from. I told him where I get them and he said ok. Then he tells me well the coupons expire today so I can not take them. I have been to other family dollar locations and I have never been spoken to the way he has spoken to me. You can clearly see the annoyance on his face when speaking from the moment I put my things on the counter. When I told him they take my coupons at the other family dollar his response was well I close in a hour.