If you enter the wrong password for your Servicing Director user more than the number of attempts allowed by your Servicing Director Security settings, then you will be locked. Once a user is locked, then the system will not let you log in as that user until the lock is cleared.
A Servicing Director user who that is not locked, and who has administrator access to the System Administration > Security Setup screen should unlock the user:
If you don't know the password for the user, review Clearing a Servicing Director User Password from Related Articles.
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