Unhappy Customer

am really unhappy with the service I received at the Keywest pick n pay. I had a trolley full of groceries ready to pay for at the till. After the teller scanned a few items I noticed a price difference with two of the items (evox whey protein). I complained to the manager and went to show him the price on the shelf. I even took out a picture showing that it was marked for 199. I waited about 45 minutes at the teller for the manager to resolve this. He eventually said that the items were packed incorrectly and there was nothing he could do. I do not see how it is my problem if items are packed incorrectly. The price on the shelf should be what I pay which I explained to him but he would not understand. As a loyal customer to the brand I will never shop at Keywest pick n pay again.