Mr Delivery *****ing our money!

So yesterday we decide to order pizza via MrD app. While busy placing the order the app automatically just put the order through and account was debited for the amount, without us even selecting "continue to payment". When trying to check the status of the delivery of trying to put the order through we got an error message saying " We can't confirm your order right now" so my husband decided to call the store to check if the order went through. They did confirm the order their side and all was in order. A few minutes later we got a call saying that two of the same orders were placed so he told them we only placed ONE order and they should CANCEL the other order. The driver then shower up at our gate and when my husband went to receive the order they brought us 6 pizzas!!! We argued with the driver saying what must we do with 6 Pizza's? Over R600 worth of pizzas, we did cancel the order yet they still charged us for two orders. We took this issue up with MrD as the problem started with their app, now they refuse to refund us our money. No one is accepting responsibility for this mess up and how many other people haven't had this same problem and who are being con'd put of their money. MrD *****ing money from us and we won't be leaving this matter like this!