Where should I enter my Steam ticket number?

Hello everyone, my Steam account was stolen and I'm in trouble with support. I've just received a response. I usually get one response per day. I just received this. Please create a new support ticket and use the original Steam account email address as the contact email address. Make sure you've logged out of all Steam accounts before creating this ticket. Also, please reference this ticket number in the new ticket.

If you no longer have access to the email address in question, please contact your email provider to restore it. I have access to my email address, but where should I enter this ticket number?