Charging more than special price advertised

I bought two of the R39 pie and Switch special deals and was charged R80, that amounts to R1 extra that I was charged. I find this very disturbing as when I enquired to the lady operating the till she info me that is how he till is set. If you take an additional R1, in my case R2, from every customer it adds up to quite a lot at the end of the day I presume. This was my first and last time making use of this shop. Be aware that the specials advertised are not what customers are charged, it is ******** in a sense. R1 or R2 may not be much but it all adds up at the end of the day. I see this as extreme dishonesty and you will never see me again. I am also spreading the word to other family and friends about this so called "special deal".