I've got an issue when running cronjob to sync users through LDAP.

Here is the line I requested manually via PUTTY SSH:
php -f /var/www/html/auth/ldap/cli/sync_users.php

---------
And Here is the response I've got after a couple of seconds:

Database transaction aborted automatically in /var/www/html/auth/ldap/cli/sync_users.php
Default exception handler: Le nom indiqué comporte des caractères non valides Debug:
Error code: invalidusername

• line 49 of /user/lib.php: moodle_exception thrown
• line 954 of /auth/ldap/auth.php: call to user_create_user()
• line 63 of /auth/ldap/cli/sync_users.php: call to auth_plugin_ldap->sync_users()

!!! Le nom indiqué comporte des caractères non valides !!!
!!
Error code: invalidusername !!
!! Stack trace: * line 49 of /user/lib.php: moodle_exception thrown

• line 954 of /auth/ldap/auth.php: call to user_create_user()
• line 63 of /auth/ldap/cli/sync_users.php: call to auth_plugin_ldap->sync_users()
  !!
  Potential coding error - existing temptables found when disposing database. Must be dropped!

The warning is in french. It means: the name includes invalid chars.

How do I bypass that error to make the system complete sync?

Thanks!