Developer account under 18
You need to wait for the activation email — there's nothing else you can do and trying to contact anyone else until then may cause confusion. You used a different name than the name on the card used to purchase the membership, so you will need to complete another activation step. This seems to be manually initiated and you need to wait for the email, which may take up to two weeks.

You will be given further instructions which may include information on cancelling the membership and being instructed to pay using a card with your own name, which was the final resolution in my case.