In the scenario in which When the network topology is a Resource/User forest, in order properly to retrieve the relevant information the connection string of the resource forest must be queried first thus . Thus it needs to be configured first in the LDAP settings in the Access portal admin siteAdmin Portal.
The second connection string will be the User forest connection string.
Additionally, In the maintenance service the following feature need to must be enabled:
Settings → Maintenance Service → Active Directory section → Synchronize SIP addresses from AD → Yes.
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