Hi Chris, thanks for getting in touch.
An email account can be locked for numerous reasons, sometimes it's due to the email user not having an active broadband account any more, sometimes it's due to issues with spam.
In many cases resetting the password to something new/never used before then waiting at least 10mins before trying to access it again is all that is needed to fix it - if that doesn't help please get back to me via PM and we'll do all we can to help.
Tom
