Paid more then the advertised price

I am dissatisfied with the service at Truworths. I went back to the store after I noticed at home they charged us more than what the item was labelled at. The manager however did not want to rectify it for the price it was marked for and told me about the fact that they can use their discretion and it was a human error. I told her it was not my error but their mistake and it was not the only item of the sort that was marked down at that price. I was upset firstly because I had to go back to the store on my own expense for their mistake with time I could have spend better. Secondly according to me the customer must pay what they see, otherwise it is false advertising. The area manager apparently said she can only offer me a R100 off which than will force me to pay more than what the first mark down price would be! We were basically forced to pay R60 more then the advertised price. I am really disappointed and will think twice to support your store again.