Uber Eats overcharging

Watch out for their promos. They will ***** you over. I received an email and promo for a KFC meal, and figured why not. Ordered the meal, app**** the promo, on checkout cost was R107.40 excl tip, which I then accepted. Then to my surprise they charge my credit card with R149.90. I have requested them to fix this as I would not have ordered the meal if the promo did not apply, as they changed the promo code app**** to the purchase without my knowledge, and they are refusing to do so. That is ******** behavior to charge my credit card with an amount I did not authorize!