See the getting started FAQs.
They explain, among other things, how to get a new SIM.
If you are already a 48 user then you'll need to order the new SIM for your son using a different email address and account/login.
Every 48 SIM requires a separate account and email address/password login.
And when you activate it and buy the first membership plan you'll also have to pay the one time activation fee of €12.99.
If you need to contact 48 support about any of this then see the links in my signature below.
By the way, I had to merge your three threads/posts into one thread.
There's no need to create multiple threads about the same issue.
