So, having had your representations to the council rejected the next step is to either pay the amount they want, (discount re-offered), or register an appeal at London Tribunals.
Your representations to the council consists of a single sentence, "the contravention did not occur". So why do you think the contravention did not occur ?
The latest GSV view of the location is February 2023, and the signs are not shown, so this restriction is newer. In the absence of any GSV view, we really need to see photos taken by you and the council. The time of the alleged contravention is 08.44, well inside the morning restricted period than ends at 09.15.
However the video shows you seemingly reversing out of a property, or maybe making a 3-point turn, then driving past the signs, except that we can't see the sign you drove past, only a sign for the other direction.
So, the bottom line is we need to see the back of the signs in the video