Manager is unhelpful at SK Promenade

On Friday 11 October, I received an email from Ster Kinekor informing me that i was able to watch a free movie due to it being my birthday. Yesterday (Sunday 13 October) I went to Liberty Promenade to use my free ticket to watch Hustlers. Please keep in mind i hardly watch movies at the cinema because it is so expensive, and the only reason i went yesterday was because of the email i received. When i got to the cinema, they told me that basically i did not have a free movie and there was nothing they could do about it. The manager on duty, Von, was extremely unhelpful, considering i had driven out of Muizenberg to come and watch this supposedly free movie. where i ended up having to pay for myself and my friend, and get snacks at the concession stand, and ended up being late for the movie because of trying to sort the issue out. Where is the miscommunication in Ster Kinekor, that allows an email to come through on my birthday telling me i have a free movie, but all my movie cards are set to different birth dates. If the manager on duty could not assist me in this regard, who can help me?