Sonic Drive-In review: Food order / refund

My order was a #2 super sonic meal-a double cheeseburger with fries & med order of mozzarella sticks w/marinara sauce, route 44 coke. Total-$13.26, No receipt. I gave waiter $14.00
What I got was a #1-single cheeseburger meal w/fries, med mozzarella sticks, route 44 coke. I Never left the parking lot. I Drive back around to window, tell waiter order was incorrect, waiter tells me to pull down, waiter comes outside to my vehicle, takes only the burger inside building, shortly comes back to tell me that I was charged for a number #1- single cheeseburger meal. I clearly stated again that, I did not want a number #1, quickly trying to resolve the issue, I ask for refund of the meal only, but will pay for the mozzarella sticks. Waiter goes inside building never came back with my money. I waited 20 mins, then called inside to speak to on staff manager while still in parking lot of sonic. I Explain to manager the issue, manager sees my order, & recites my order to me while on the phone, then says she cannot do anything w/o my receipt. I tell manager, I never received a receipt, and that I just placed my order, & that I was still in the parking lot. Manager states again she can not do anything w/o a (my) receipt, and hangs up.