Can not enable 2FA?

So since there is the 50% sale right now I would like to gift a friend of mine a few things, but the problem is I can’t gift him anything because he needs to enable 2FA first.
When we wanted to enable it for him everything was kind of “greyed out” he could not press anything under Security Settings except “Verification questions” on the gaijin website, not even verify his E-Mail.
He plays over steam and logged in on the website over steam.
I’m not sure if you can access those settings when logging in through steam so he just made a Account on the Website with the same E-Mail. He has the same purchase history on his account and can now access the Security Settings but when I gift him something he does not receive it in-game after claiming it through the website.
Did we miss something or did we do something wrong?
I would really appreciate anyone helping

bump bc im confused as to why mine is also greyed out

You need to go into war thunder, your player card, then bind to email at the bottom of the window