Euro Car Parks

Received a penalty notice for £85 today for allegedly parking in my local Morrisons for 4 hours a couple of weeks ago. Its not a pay and display and is free for customers-I don't even think I was there, but if I was it was for 10 minutes tops!. I asked in Morrisons today about how my reg was captured ,they said there are no cameras in car park ??. The picture of my reg on the penalty notice is just of a number plate no image of the car and staff at the store have told me several people have asked the same thing. If I was in the wrong and had been there for 4 hours instead of the maximum 2 that is signed posted I would have paid. I only live a 5 minute walk from the shop so only park when I am getting more then a carrier bag full. It's ridiculous !!! they won't even answer the phone to talk about it. I have emailed them and siad I am happy to go to court, and have asked for further proof.