Another Disappointment

On 23/12/15 I went with my family to watch Star Wars. We were a party of 7. My boyfriend and I wanted mega combos. We placed our order for 2 mega combos with cokes only to be told there were no mega containers. So We settled for 2 classic combos with cokes. We paid and only after payment had been accepted did the cashier tell us the coke wasn't working. This after I had twice stated we wanted coke. We were then told we could take either a slushy or water. We chose a slushy which I will never have again as it was disgusting. Is it really so difficult for Ster-Kinekor employees to communicate to their customers the technical difficulties they are experiencing before the customers pay?