Hi @Bharat Kumar Hazar Hazar (iCORE-CRS)
Thank you for posting this in Microsoft Q&A.
I understand your concern regarding the default checkbox of Identifier (Entity ID) using Microsoft Graph API.
By marking this default checkbox for Identifier, it means that it is a primary identifier.
Unfortunately, Microsoft Graph API doesn't have a specific property to mark an identifier URI as the "primary" one.
Hope this helps. Do let us know if you any further queries.
Thanks,
Navya.
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