The email sent by CB is as follows.
Key: UE_USERNAMEREMINDER_MSG
String:
Code:
Hello,\nA username reminder has been requested for your %s account.\n\nYour username is: %s\n\nTo log in to your account, click on the link below:\n%s\n\nThank you.\n
Key: UE_NEWPASS_MSG
String:
Code:
The user account %s has this email associated with it.\nA web user from %s has just requested that a new password be sent.\n\nYour New Password is: %s\n\nIf you didn\'t ask for this, don\'t worry. You are seeing this message, not them. If this was an error just log in with your new password and then change your password to what you would like it to be.
So yours has already been overridden or maybe translated if this is was originally in a different language. You can use the above language keys to override the forgot login emails though.
You can also completely turn off CBs forgot login process and use Joomla's. In the future CB won't provide forgot login anymore and will exclusively use Joomla's. To do so within CB > Configuration > General set "Forgot Login Method" to "Joomla".