Ubereats Poor Service

I ordered food via Ubereats over the weekend, specifically because of the buy 1 get 1 free promo that is currently running. In my notes on the app, I clearly indicated the above-mentioned, so as to ensure that there aren't any errors made. Order arrived with only 1 meal, which I then refused to pay for and sent the driver back with the food. I was then told that my specific order was not part of the promo, which is fine, however, they should have informed me of this before proceeding with the order, especially since I clearly indicated twice on the app that I am expecting a mealx2. Ubereats is now demanding that I pay for a meal which I did not receive and feel that on the day, they should have contacted me to let me know 1: meal option selected is not on promo 2: after the meal arrived they could've contacted me to let me know that if I refuse to take the meal, that it would still be charged to my account. Instead of having automated responses, they should employ agents that can actually attend to individual queries/complaints. I would definitely advise that customers opt for the cash option at all times, so that Ubereats do not have access to anyone's banking details and if you are unhappy with their services, that it is as simple as just deleting your account with them.