False Advertising With Bad Attitude

I just went to KFC in Pelican Park Cape Town, I was helped by Yandiswa I then asked for three am mini Twister's that was advertised at R14.90 each, after she took my money she then put it through the till for R21.90 each,I then told her you over charged me she then said know they made a mistake its not there problem the advertising is wrong, please see attached pic I'm so upset with this staff they just spoiled my day after I am such a good client of KFC, how can you put up false prices and not help a customer when you are in the wrong I'm appalled by the customer service I was given,after I asked if can get it for the price advertised they all gathered at the counter saying its not them that put up the adverti*****ts and i wont be helped for that price,i am very disappointed in the way is was treated. Please look into this matter.Thank you .

Regards Mr Smith ********** 521