Tips: Azure AD B2B user UserPrincipalName(UPN) update

Issue:

Trying to update the UserPrincipalName (UPN) of B2B user to some public domain email address like siva@gmail.com in Azure AD tenant and results below error message.

Error message - "Property userPrincipalName is invalid"

Solution:

Make sure create/update user UPN with verified domain names in Azure AD tenant.

Thanks
Siva Pokuri.