I am taking this further and finally have a notice to owner. Do I have to tick 'the alleged contravention did not occur' or 'the order of contravention is invalid' or 'other'? Thanks

The part in quotes (1st post) from their rejection of the informal challenge implies that everywhere without white lines or numbers is not a 'bay area' . I don't know if the others got a ticket.

Because its not a parking space at all - not counted as a bay

Sent an informal challenge to council indicating I'd bought a ticket and that the area I was parked in looked like a legitimate area to park in and I was not causing an obstruction. I had to tell 5 other people not to park next to me as I was gathering evidence showing that the floor markings were confusing. My informal challenge was rejected saying that "every bay in this car park is marked by white lines and is numbered using large painted letters". The definition of a parking bay on the Collins online dictionary is "a space in a car park designed to be large enough to park a vehicle in". The space I was parked in was certainly large enough to put 3 small cars, and the floor markings made me think (and many others) that this was a designated space. There were no signs to say otherwise. Residential "bays" on roads are long and thin and not necessarily spaced individually for cars. Do you think I should take this further with an official challenge arguing this point / the lack of signs / or the slightly damaged sign indicating that this is a penalty in the first place? Any help fighting this will be much appreciated. I've never fought these bullies before trying to kick my rice bowl away.