I'm trying to allow my son's email account - the "verify you're an adult" stage keeps failing with the message:

When you verify your age with a credit card, Microsoft charges the card a one-time fee of $0.50 (50 cents), and a portion of the fee is donated to charity.

Our system is temporarily unavailable. Please try again later.

If the problem persists, please contact customer support.

(40101-[2]-a9977319-f89c-4066-9254-acfae5d315b9)

I tried yesterday and again today but it is still failing. Can this be fixed please?