FALSE PROMO

I Placed an Order on Monday. KFC had a Buy 1 get 1 Free. I Added the Items to my Cart, Discount was Given. But as soon as i Placed the Order the Full Amount was Deducted from my bank with no DISCOUNT! I immediately got help from the App the Agent said, he cannot help me right away i must have them complete the order. I asked him will they refund me and he said Sure. But i am not hearing anything from Uber Eats.