Family Dollar

I came into the store today to purchase laundry detergent. They didn't have the shelves stocked. All the boxes were just sitting there. So I had to grab the biggest size they had. The smart coupon said $2 off. When I got to the register my coupon wasn't being added. I had to reset my password and the app was taking forever to load. After 30 minutes of being in the store, I was irritated like anyone else would be. The GM comes to the register and I explain to him the app wasn't working. He starts yelling at me in front of other customers that the app does work and that I'm just too stupid to work it. After him trying it and saying sometimes it works and sometimes it doesn't. I jokingly made the comment, "oh so the app doesn't work!?" He got even more mad and irrate and refused my sale and told me to get out of the store. I have NEVER been more humiliated and embarrassed in my life. I left crying. I want a follow up call from his manager as this is NOT OK. No employee, a GM at that should yell and belittle a customer that comes in every day. GM name is Bradley. When I told him I was going to complain he yelled at me again and told me to go ahead. Which means he has gotten away with this before. I am requesting a call back asap.