WRONG PRICING

I purchased Dog food which was on special however when i checked the receipt when i got home - I found that i had been charged the normal price. I checked the pamphlet and it too showed the special price. I also found other items that i was charged the normal price for. Its enough we spent a long time in the queue but are we expected to check every single item at the counter. I spent a total of + R5000 on the 29th August.