The Broker appliance has been configured to utilise Active Directory as the authentication and identity source. When an administrative user attempts to activate new users, the user list doesn't display all users to select from.
Active Directory introduced a queryset limit to LDAP queries, resulting in a limited number of results being returned to the Broker. This limit is 1,000 by default.
Although it is possible to change the default limit, Active Directory administrators should be consulted prior to making this change.
Buttonwood has implemented a change in the Broker's behaviour to paginate the LDAP request to work around this limitation.
Please update the Broker if this issue is identified. Refer to the article Updating the Broker for detailed steps.