"Parking fine"

Had an appointment in Cardiology at Royal Glamorgan recently. Been having chest pains for years after a quadruple by pass. I drove around the car park at least 5 times bot could not find a space. Had to park on the road, many others there, There were no yellow lines just a sign saying no parking on the opposite side. In the actual car park there were dozens of cars parked outside of the allotted bays which made it hard to drive around. Had to do this not to be late for my appointment, I had a £60 fine notice on my windscreen. In a similar incident 3 months ago an attendant told me it would be okay, that they had some common sense when there was no room. I was causing no obstruction. The company is PCN Parking Solutions. Their no parking sings had no indication whatsoever of their company's name. I have appealed to them and am waiting to hear.