Off Yoghurt from Take n Pay

I purchased a 1kg fruits of the forest yoghurt on Saturday from Take n Pay in Westcliff, when I arrived home and opened it I noticed that the seal was broken and the yoghurt was slightly discolored and off. this isn't the first time i purchased off yoghurt. I called the store and spoke to Aliya who said she will get the manager to call me however i am still waiting.