Bad customer service

I'm very disappointed with the service I received at Debonairs North Beach, I sent my daughter to buy pizza and cold drink 1L or 2L she accidentally bought buddy, well since we were still within the store I asked them to change and we will add money, the cashier that she bought from started giving my teenage daughter attitude saying she won't exchange it, so I asked for the manager who also gave me an attitude and after a long wait she decides to exchange the cold drink but their attitude really stink and they are in the center of a tourists junction the lady I'm taking about worked at till 1 from the fridge around 3pm