"Parking con"

I parked at 12 noon for atwenty past appointment. I was seen at ten past and upon returning to my car at 12:15 I found a parking ticket. I had seen the sign which stated first three hours free followed by pay and display. Having read this and knowing I would only be a short while (half an hour at most) I proceeded to attend my appointment. The sign is misleading and takes advantage of people who have conditions or worries about attending a hospital. I gives the impression that you only need to display if you are going to be there over three hours. When I found the ticket the vultures from smart parking had left I got upset. An older couple came over and asked if I was ok, to which I explained my situation. They were about to do the same as me having interpreted the sign the same way. I would have rather you charge so in forced either way to go to the machine than being caught out in this way. Maybe your receptionists could explain to each person when they register in as I'm sure im not the first to be caught out and won't be the last with the current signage.