Parked in short stay car park for long weekend after booking online as the cost was not much more than long stay. I think I paid @ £33. On the way out, after inserting my ticket the barrier wouldn't open and the display indicated I had outstayed the ticket period which was incorrect and was told to go to the parking station. I didn't fancy the walk all the way down to the long stay so hit the "help" button. The staff were fine and said that the camera had failed to read my number plate on entrance due to one of the screws on the plate. Never had this issue before with the same car. But they raised the barrier for me. A bit inconvenient but no big deal.