Free Traffic Legal Advice

Got a PCN but didn't notice the top sign it's very high up and didn't even fully understand it as it doesn't say 'no parking' and just uses the logo.

I did see the bottom sign and it was fine to park as I was outside the residents parking only hours.

Is there anything procedural for challenging this?

This is the exact sign.

https://maps.app.goo.gl/Hpi3YCCochcdJ3sa7

NTO has been received.

The top plate is a standard timed no waiting sign. I can't see you have much hope here.

+1
Knowing these signs is fundamental to when you are considering parking your car on-street. The only thing I can see that might help is the yellow line is not continuous in the parking bay on the GSV view of 2023. A yellow line must be present to indicate the extent of the restricted area as indicated on the sign. As here on GSV 2021 

You  have posted the original PCN, and not a Notice to Owner that is always sent by post to the named driver and address on the V5 for the vehicle.