Looks like this is a fairly new restriction because it isn't shown on the latest GSV view of 2022. The junction view is 2018 !!
The usual way to fight these is on inadeqate or even missing signage, but with nothing on GSV, you will need to do some legwork and take photos of the signs as you approach the junction. Are you able to do this ?
There is a video on-line on their website; this is the sole evidence of the contravention. I looked on their website and the video shows you turning right out of Gordondale Road into Lucien Road. The signs showing "End of pedestrian and cycle zone" can be seen. The "Flying Motorbike" signs barring your entry will be on the other side of these. So what we need to know is, is there any advance warning sign as you approach the T-junction. If there isn't, your case to take them to adjudication is much, much stronger, because the signs are right on the junction as you turn when your attention is, rightly, elsewhere.
So, OP, more info please.
There may also be a "technical" appeal available based on the council management of the enforcement process and content of the PCN, but I'll leave this aspect for those much more expert than me.