Have you checked LDAP for any feature group? System - LDAP - LDAP Directory. I'm not sure how many you have (probably 1) but check it (or each if more than 1). Under "Group Information" will be a field called Feature Group Template. If there is an entry there, go to User Management - User/Phone Add - Feature Group Template. Find the template listed in the LDAP directory and see if the Home Cluster check box is selected. If so, you found your root cause.
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