Microsoft Entra ID: How to Provision Users
New users cannot be created in a domain that has already been federated in Microsoft Entra ID. Instead new users must be created in a non-federated domain and then migrated over.
In addition, before the migration, users will need to be assigned an ImmutableID that will be used to provision them inside of Forcepoint ONE SSE. This guide page will walk you through the full steps of creating and provisioning users when using Microsoft Entra ID.