Pick n Pay Hypermarket do not keep there promises

I was charged for than 50% more than the marked down price for cheese from Durban Pick Pay Hypermarket.Have been trying for 10 days to get Pick N pay Customer services to give back double the difference which is there guarantee but to no avail…all i got was a a few reference numbers . What a useless organisation they have become .No wonder they have lost so much market share to all the food retailers in South Africa and it looks like its still going to get worse !!