Kfc ringed up my order twice and gave me cold food

Kfc grassy Park ringed my order twice and then on top of it gave me no chips. The cashier ringed up my order twice by mistake and promised me that they will pay the money back into my account within 24 hours, I've been waiting 3 days now and still nothing. I went back today and it was a total wast of my time and petrol to drive there as they still could not help me. I provided them with my bank statement as proof bur still I have to wait another day. What about me and the time I wanted and the fact that I got no chips with my meal?