ABSA voucher redemption at BurgerKing not understood

On 27 March, I tried to redeem an ABSA voucher at BurgerKing Northmead. I was helped by Thivhazuni. When placing my order, Thivhazuni told me of a 2 burger special. He wasn't sure of the price but the 2 burger deal sounded good and I changed my order. When the order arrived and I had paid and had the ABSA voucher redeemed, I found the "special" cost R230! I told him that I wanted to change my order to my original request. He said he could that but that I would lose my voucher value. I asked for something else to the value of the voucher but he said that I would be *****ing then? Eventually his 'manager' arrived to try and sort the issue out. He was even more confused and even had one the other ladies trying to explain the situation to him. But he was too arrogant to even acknowledge his ignorance. He didn't even know what a wiCode was for the voucher redemption. He then said I was lying, I was told what the cost would be! My daughter, who was standing next to me and I both heard the wrong thing? Not sure if ABSA want to be associated with this Burger king. I was eventually forced to reluctantly take the "special" or lose my meal. I could not even get a refund or else I would have lost my voucher.