Family Dollar complaint: Furious and disgusted

I was in the line and made a purchase with the option to get cash back, I chose 50.00 cash back without noticing the sign that stated NO CASH BACK neither was I informed by the cashier after letting her know I was using debit. The cashier rudely said I just came on I don’t have it in my drawer. So I said so what do I do. She said it was nothing she could do and called the Manager. He already seemed bothered he was so rude like It was a personal matter. He telling me you should have read the sign and it’s nothing he could do and that they don’t have the cash he was disrespectful telling me it was my fault anyway so he don’t have give me anything. So I asked are they taking it out of my account, Robert the manager and the cashier both replied yes but they don’t have it and they can’t refund it. So now I’m just offended and taking back by the way he’s approached the situation. After I requested his supervisor he then tells me very rudely your gonna just have to wait to get your cash tonight. I said I’m not leaving without either speaking to a supervisor or a refund or the cash that was approved and withdraw from my account. While Robert calls his supervisor the cashier says to leave my info.. So now I’m signing the paper giving my info and i hear Robert lying to the supervisor right in front of me and tells his supervisor that I don’t want to leave my information and refusing to leave my number. At this point the supervisor must have told him to give it to me. He’s pissed and really snaps on me and also stating to a customer rudely that I can’t help you because of her. And I tell him he’s very unprofessional and rude the whole time I’m talking to him he’s ignoring me saying HE DOESN’T CARE about 7 times. I told him I would call the police if need be to resolve this issue, he laughed and said … You would ! He tells me several times don’t come back to his store he’s gonna get a trespassing warrant on me. He started taking pictures of me. I told him and her the only thing I did was not see the no cash back sign and that I’m allowed to make mistakes. I told him that this was not how a manager should treat a customer and once again he was rude and once again he said he doesn’t care