overcharged on R100 speacials

I am some what very disappointed in Makro, they are my favorite stores to shop at and do shopping once a month at your store , i was over charged on a number of R100 specials cuddlesr nappies and wet wipes together was R100 as advertised, when i got home checked my slips (as i had a baby with me i could not do so in the shop) i saw R180.00 for nappies and R24.00 for the wet wipes, the purity i was over charged etc this is unacceptable as i rely on the R100.00 specials as a savings bennifit i am highly dissapointed in makro and think that maybe going to another retail store would be cheaper as i dont get overcharged on their specials