Product at wrong price label

On the 21st October my fiance and i went to the Pick n Pay in Kenilworth Center. We went to buy a few things for son's lunch box. We saw the cashew nut and saw R7, 99.We thought it was a reasonable price so we took five packets. When we got the till it scanned R13, 99,my fiance with one of the employees went to check on the shelf to confirm the price. They saw that the product was packed above a label for something else and there was no label for the product at all. The cashier called the supervisor, by that time I had already paid for my things. We explained to the supervisor the situation and she took us to the customer care service desk.When we got there she explained the situation to the lady sitting their. They say that they must speak to a Maruwaan. The supervisor went to look for him. He came and basically told us that there's nothing he can do.We then,again, explained to him what had happened. He still adamantly said that he couldn't do anything, even though the product was packed on the wrong place and there was not even a label for it also. I then got in touch with their customer service via fb messenger. Initially they were quick to respond and said thay they would get back to me when they were done with their investigation. I sent them a mssg again yesterday as i felt that it was taking long for them to get back to me. This morning, 26th October, i received a reply stating that my query was closed, with a response form the person i dealt with in store,attached. I want to know is this fair practice.