Barnoe

Thanks for all your help everyone lol
 
Update and solution
for the benefit of anyone searching for answers.

Get the person who is NOT on the local network ie connecting remotely to download an app on their phone called "Bedrocktogether"
Tell them your external IP address to your home/router and the port number your minecraft server is using.
(make sure the port is forwarded on your router)
When they click connect it will play a 30 second advert after which they can keep the app running but close the screen on their phone.

Go onto their Xbox/Playstation and look and friends and scroll to the bottom and they will see a "BedrockTogether" game........connect
 
Job done.

Its a workaround and seem like an hassle but it works flawlessly.
My son and his friend are happy as the proverbial pig in ####