Pricing of items incorrect

I was now at pick a pay brandwag and saw that there were any 2 pnp pizza with 2lt coke for R80.00. so I took 4 pizza and 2 cokes, got to the till and the lady said to me its not valid. went and got her the price to show her, then she talk to 2 other ladies so that I could not understand what they were saying in shoto. Then they come with no the pizza must be the same grams. but hell there is no sign that shows it must be the same grams. it only shows 2 pizza with a coke for R80.00. I totally lost my temper and walk out without what I wanted. There were no good service and what made me mad is that they were talking in there language so that I could not understand