If your able to login to firefox account registered to that email you should go to preferences and change your associated email address there.

I called for an administrator.

If you no longer have access to the old email address then your only option is to create a new Firefox Account with an email address you can confirm. *https://support.mozilla.org/en-US/kb/ive-lost-my-firefox-sync-account-information ---- For future use, see also: *https://support.mozilla.org/en-US/kb/change-primary-email-address-firefox-accounts *https://support.mozilla.org/en-US/kb/add-secondary-email-address-firefox-accounts