I tried to pay at the payment machine and my number plate was not recognised, so I left / was told by security to leave, why did I get a PCN?

In the event that a Payment Machine does not recognise your Vehicle Registration Mark (VRM) when you go to pay on exit from a car park, it does not automatically mean that you won’t then get a PCN from PCPEA. 

It is the driver's responsibility to make every effort to pay for parking on private land and if the machines are malfunctioning, seek advice from site staff or the machine itself to resolve any issues you are having whilst still on site.

PCPEA use separate cameras to manage the enforcement of the car parks, meaning if we are not informed by the payment machine operator telling us about an on-site incident, you will likely get a PCN if you leave without paying as our cameras will have picked up your VRM correctly. If you appeal against a PCN, we will check the data from the payment machine operator and if your VRM is not found on their system or a list of exemptions, we will accept your appeal and void your PCN.