To request your refund within 24h of registration you must click the refund link provided in either the confirmation email or the receipt email.
Upon clicking on the link you'll be redirected to the order detail and the refund request window. If you do not have a user account on World's Marathons already, you'll need to create one first to access the order details.
Upon request, your order will be processed for refunding.
When it's processed you'll receive an email informing that the refund is complete.