BROWNIES TASTE HORRIBLE

I recently purchased a Choc Brownie SS Ice Cream from KFC in Rooihuiskraal. Only to have tasted it after I left the store , the brownies had an extremely funny taste as if though it was expired. It was purchased on the 02-April 2018 of which I still have the slip. There was definitely something wrong with the brownies and I am hoping it was just a problem that day and at that store as the original choc brownie avalanche used to be devine.