If your admin account is Locked and you do not have any other admin user to login, then you need to move with reset password of admin account, once you do that, you make sure you have other alternative admin account to mitigate this kind of situation.
https://www.cisco.com/c/en/us/support/docs/security/email-security-appliance/117866-configure-esa-00.html
This is not what i have described is correct. please let us know.