Hello,
Lately scammers have been posting   (mainly in threads where no reply has been posted yet),   claiming to be Mozilla experts and asking users to either call a so-called toll-free phone number or giving them a link to a site, where they are promised to get expert help.
These posts of course are scams.
Hopefully informing you about this will scare them off and you won't see such scam post.

If you have received a message that your Firefox account has been locked

First wait 24 hours until trying again. If it fails again and you still have access to the email account, then please create a bugzilla.mozilla.org account and use this link to create a request.

This is when your account is locked and you do not have access to the email account you created this Firefox account in, or the email is no longer accessible. I would recommend making a backup of your local profile first and then creating a new Firefox account.

To read the full instruction, please see this article.