Not happy

Wanted to have a new tyre fitted. Sales person Thomas quoted me R 500 for the tyre BUT they are running a promotion. If I download the Tyremart app, I get R 200 discount and will only cost me R300. The app was downloaded instore which obviously incurred some costs for me in terms of data but when push came to shove, it seemed that the promotion was only valid for August. Needless to mention I cancelled everything and left as this internal communication slip ups and selling non valid promotions , definitely not on.