Sorry bro but we do not have your Google Account password so we can't help you.

This forum is only for issues related to Mozilla Firefox and is NOT for changing people's email ids.

If you are having trouble changing your email id in Firefox, try restarting it in Troubleshoot Mode. You may do so by clicking on the 3 horizontal lines below the Close button, then click Help, and finally click Troubleshoot Mode.

See this article.

https://support.mozilla.org/en-US/kb/change-primary-email-address-firefox-accounts