Gold Reef City Watch what you get

I received 4 complimentary tickets to the theme park from my gran. Unfortunately I only received these tickets last week Wednesday, but was very excited to tell my kids that they were going to Gold Reef City. I read on the tickets that they were only valid for the month of November. So my husband and I got the kids ready to go on Sunday (the only available day I had) and off we went. When we got there outside of the gates was a big sign saying closed for private function. I was told by the security that I should have gone onto the website and read it. WHO GOES ONTO A WEBSITE BEFORE THEY VISIT A VENUE? I called through to the Marketing department to see if we could please get an extension for just 2 weeks even for a week. And I was told NO. it was for November only and we arent budging. I am being blamed for receiving the vouchers late and that there was a private function. Thanks for nothing Gold Reef. Wont be visiting you ever.