Hiya. The Code is 01

Hi all I'm new to this place so apologies if I'm doing something wrong! I received a PCN yesterday for parking on a double yellow line that I am clearly not touching or overhanging. Perhaps there's some other rule that I'm breaking that I can't find in the highway code. Any assistance would be appreciated! On the face of it, I don't think I'm in the wrong here considering also that I've park in exactly this spot most days of the week for the past 2 years without incident. Thoughts? Rob