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I parked in a residents permit only bay in camden, London using a blue badge. I was surprised to then find weeks later i got a PCN.  The letter from westminister council stated I did not display a blue badge and that a PCN was attached to the car. However the photos the council took of my car do not show any PCN attached to the windscreen. I did not find any notice on the car when i returned to it either on the day otherwise i would have dealt with it much sooner. In fact they actually show what i think is the blue badge on display in the front on the dashboard just behind the windscreen. See attached photos. These were taken by the PCN officer supposedly. I also included the sign showing the parking restrictions for that bay. My mothers blue badge is issued by barnet council. The bay is a shared bay between camden and westminister. They have differing rules on blue badge usage for residents permit bays. Westminister does not allow but camden does. So I took that as being ok to park in as camden allow blue badge for those bays. Anyway what i want information on is what should i do. I have been offered the lesser fine of £80 to pay if i pay early. I appealed the notice once but was rejected as the letter stated i had no blue badge displayed. In the councils photos nothing is clear. Normally they take photos of the PCN notice attached clearly to the car before they leave. They just took some long distance shots with unclear photos of the windscreen and no clear photo of the PCN attached to the windscreen. Should i appeal using the tribunal option they have? What is the best option in this case. I 100% believe i did place the blue badge on the dash before leaving the car and there 100% was no PCN attached to my car on returning.