Woolworths Quality

This weekend I purchased a Ham and mushroom pizza from Engen in Veldenvlei Richards bay at the woolies in-store. When I got home the pizza was layered with mould and I returned it the next day for a refund, I was not given an explanation as to why this happened. I also went through the food section and noticed quite a few of the foods were starting to change color and clearly something was wrong. In ten years I have never experienced this bad quality from Woolworths. I feel action needs to be taken as I purchase at that store regularly.