There is a chance that you clicked on your individual ticket link more than once. This causes a 10 minute freeze on your ticket link. This is a safety precaution to avoid sharing of your individual link.
Please wait 11 minutes. Click on the link again (once). Then this should direct you to the live Ticketbooth checkout.
Please do not stress - your link will not be released to the public until 10:30pm.
Good luck with your Rego!