McDonald’s complaint: Wrong order

So I ordered Hotcakes and sausage and a large orange juice. When I pulled up to order there was a previous order on the screen and seeing a large orange juice for $1.89 helped me to decide to order. My order NEVER came up on the screen and they told me it would be $9.20. I couldnt figure out why it was so much. When I got to the window I asked why it was so much how much was the hot cakes and sausage and she told me $5.79 and the Orange juice was 2.89, I asked why it said the orange juice for the previous order was 1.89 and her reply was she had no idea their board is weird. I got to the window to pick up my order and again I said I had hot cakes and sausage. Three times I said what my order was and no one noticed I was charged and handed a big breakfast. In no way do I want all that food NOR do I want to pay for what I didnt order.