I'm aware of this gym. If you can show you attended the gym that day, you may get it reversed. The Gym have a tablet that customers are expected to use to enter their registration plates, and that gives 2 free hours. many people forget to do this. I was once done by this, but by that time they didn't even have the tablet working, and the gym tried to fob me off that it wasn't their responsibility.
at that time, somewhere on their website had "free gym parking", which is what I used to throw back at them, and they got the ticket cancelled on my behalf. I don't think that wording is on the website now since they installed the Tablet.