False promo advertising

While browsing I landed on mrprice website and saw a pop-up promo offering R100 off your first purchase of R500 or more. I entered my email and received confirming email from mrprice. When I placed order however, discount was first allowed and then deducted again when I continued with payment.This happened a few times. The next day I chatted with an agent who were dismissive and who told me I must send proof of promo to him. Because he had no knowledge of promo he expected me to follow his senseless "instructions" I requested that me query be reported and he refused telling me that he "already told me what to do" I then send an email to customer care who responded 2 days ago that they will check whether it is first time I am buying online from mrprice (WHICH I KNOW IT IS). Didn't hear from them since. They can keep their voucher as I don't want to do business with them again. Some people may not realise that discount is added again when they make payment.

A day after