Rotten Stewing beef

Hello. I bought groceries at Pick n pay Southgate 2weeks back. I bought Stewing beef and cooked it. We had poisoning from the meat. I regret buying it. Secondly, I bought Nescafe which was on special for R65 but when I checked the receipt it didn't deduct same goes for their house brand milk, it was on special but never deducted. I was reluctant to go back and ask why that had happened. I'm so disappointed. I will never buy at Pick n Pay again. I don't know why I stopped buying at Woolworths. Very disappointed!!! Never again