bad service, rude and arrogant

Placed an order and realized its not what I actually wanted to order. I apologized to the lady and asked if she can be able to change my order. She claimed she can't void it only the manager can. I asked her to call the manager, she took forever to return. I eventually called her out as I had waited for over 15 minutes, upon her return I asked about the manager. She responded by saying the manager never listens to anyone and is sitting in her office. 20 minutes later she came out screaming @ me, saying there's nothing she can do about the order as they have already cashed in. It was a huge argument that led to her clicking her tongue @ me. He staff was even complaining of how rude she is to them. When mentioned that I will report her she said she doesn't care what I do