Note:
"Email change or Email hint" if I were you I would rather open the ticket in this department because if I'm not wrong Lost access department is delayed.
There are four ways to create a ticket in this case,
1- The first is to clear your browser cookies.
2- Easier way is using incognito mode on google chrome or private window on firefox (private windows don't store/support cookies). and use an email that has to be attached to a xat account to create the ticket.
3- Get yourself a new id that is not registered by anyone through clearing your flash cookies, follow steps Click here then create the ticket using your email address that is tied to a xat account.
4- Login to an account of your own if you don't own another account then create a new one.
however, I would go with the first option. You don't have to be a paid user to create a ticket in this department either.
Feel free to opt for any way over the others.
Anyway if you still receive any error messages while opening the ticket not to mention any solutions you have done, you can contact with a volunteer and ask them to open the ticket for you.
Best wishes!