Taxify is ********

Taxify has promo codes that are meant to minus a certain amount off a trip. I get adverti*****ts for this via email and it shows up as an option to use these promo codes in the app. However, my card still gets charged the FULL AMOUNT when I take a trip. I should be refunded and yet taxify is not allowing this. I use taxify every single day (hence why i get so many promo codes), but i will stop giving them my business if tgey do not address this issue