deregister

I bought a new Orbi. So I gave my Nighthawk to my son. But he cannot rgeister it because it isstill registered at my account.

I cannot get it deregistered.
I sent a message to ask for help to the Netgear Support team. But get no answer.

Now I tried to ask for support again. But the website so user unfriendly that I cannot even ask such question.