@Kerryb500
If you are your son's phones are both on your account then I would have thought there will be an option to select which phone the esim is installed on so try going through this:
https://www.sky.com/productsettings/mobile/activate-sim
__________________________________________________________________________________________
If someone has helped you then please click on the LIKES button in their post.
If you need help please provide as much information as you can
