Hi @Marco vanW ,
Thanks for reaching out and apologies for the delay in response.
Microsoft Entra External ID for customers /Customer identity access management (CIAM) is a new product in Microsoft Entra to manage external identity use cases.
In CIAM, customer accounts are mostly created programmatically when users sign up through an application.
I tried to sign up the user using the application as mentioned here and was able to get the user email in the claim preferred_username as I sign-up with email.
and the same email value has been reflected in the user properties(Email) as well.
However, if you created the customer directly in the portal, then user's properties are not reflected. We are working on that, but the expectation is as CIAM is for customers, customers should self-sign up through the application.
If you are also trying to sign up the user through an application and facing issues while doing so, please share the reference link of the application you are using along with screenshots to help you further.
Hope this will help.
Thanks,
Shweta
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