Bad customer service at Burger King Hatfield

I recently visited the Burger King branch in Hatfield. I ordered two cuppa cakes. As I left the branch, and tasted the ice cream of the cuppa cake, and it tasted soapy. My friend ate her cuppa cake and noticed the same unpleasant taste of the ice cream. So we returned to the branch and informed the employees of the strange taste. And then we were introduced to the manager. Every employee who we encountered for this complaint was rude and unprofessional. They told us that we were wasting food and proceeded to complain about me and my friend in their language, thinking we wouldn’t understand. We asked for no replacement cuppa cakes, but the manager complained saying she already put the order in. This was after they took our initial cuppa cakes and tasted it, before asking what we’d like to happen. Every employee told us that’s how the ice cream is meant to taste, and when we asked whether it was because of how the machine was cleaned, they told us that the machine isn’t cleaned. It was a very bad experience. I love burger food but this service was awful. My friend and I were made to feel stupid and we weren’t even helped properly.