@Jessie Cochran Thank you for your patience, below is the response that I have got for your issue mentioned above.
the provisioning service has a limitation that it cannot provision null attributes. - https://learn.microsoft.com/en-us/azure/active-directory/app-provisioning/known-issues?pivots=app-provisioning#null-attribute-cant-be-provisioned
You can follow this workaround, by setting the email to an invalid value like "no-email@domain.com" when the email attribute in Azure AD is cleared, you can use IIF expression as documented here - https://learn.microsoft.com/en-us/azure/active-directory/app-provisioning/hr-user-update-issues#null-and-empty-values-not-processed-as-expected
Let me know if you have any further questions, feel free to post back.
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