Refund on double payment

On the 27th of March we bought KFC at the Paarl branch. The first transaction was pending and they couldn't finalize the transaction. The cashier plugged out everything to reboot the system, but the transaction went through on my phone. They have tried a second time and only then the transaction was finalized. But now I have paid double for one order. Jennifer that was in charge that evening took my details and they will try so sort this out. Long story short, today its the 14th of April and I still have not received my refund. They told me to send my bank details for the refund, but have not receive anything yet.<br> If I do not follow up with them, I will hear nothing from them.<br> I do not think this is how you are suppose to treat your customers, how can I pay for something I have not received and then I must wait 3 weeks for my refund.