Here is the phrase username_same_as_password:
HTML Code:
Your password is the same as your username. This is no longer allowed.<br />
<br />
Please change your password using <a href="profile.php?{1}do=editpassword">this page</a>.
Enter that in your Phrase Manager (it is phrase type "Front-End Error Messages") and then they should see the message and click the link to change their password.