What is 3D Secure?

3D Secure is an extra security check that your bank runs on some online card payments. It confirms that it's really you using the card.

When your bank asks for it, a verification window opens during payment. Depending on your bank, you might enter a one-time code sent by text, approve the payment in your banking app, or use another method your bank offers.

Complete the check and the payment goes ahead. If the check isn't completed or fails, the payment won't go through. Try again, or contact your bank if it keeps failing. See What should I do if my payment fails?