Draft representation:
Dear London Borough of Barking and Dagenham,
I challenge liability on the basis of inadequate signage. As the video footage shows, the street lights in the area were not working and the signs had no illumination. Having revisited the area, I note it's a very wide road and the signs would not have been in my direct line of sight.
Furthermore, the Traffic Signs Regulations 2016 require signs of this type to be illuminated.
On the whole the signage is not adequate within the meaning of regulation 18 of the The Local Authorities' Traffic Orders (Procedure) (England and Wales) Regulations 1996.
It follows that the contravention did not occur, and the PCN must be cancelled.
Yours faithfully,
Make the representation online, you'll have to do it twice (once for each PCN). Keep a times / dated screenshot of the confirmation page.