Also I've played Call of duty before and its shown my geo location as somewhere else in the country not even relevant to me.
Maybe CGNAT.
It is not CGNAT or your IP address shown on what's my IP would be different to the IP address shown on your hub.
Every BT customer is connected to a BRAS in a private address range, as you can see from the screenshot of my hub that I posted and port forwarding works just fine for me and I suspect for countless thousands of other customers.
It is not the source of your problems.
but it would always show my public IP and that site as that is the end hop.
Doesn't tell you how many nat devices are in between.
I give up, if you are not going to listen I'm wasting my time.
I am listening , just find it hard to believe I can't port forward , can't use upnp on both the routers I own.
Everything points at what I'm suggesting.
If you can help me out on what you think the problem might be then please, I'm all ears.
Now, my brother does own a PS5 also whos connected via WiFi where as I'm connected via cable. I always port forward to my PS5 IP or make sure the UPNP ports are also done to my console.
His connection (he says) is ok but could this be an issue?