Hi,
Thank you for asking this question on the Microsoft Q&A Platform.
It seems the configuration is missing from your identity perspective, do you have exact details for the IDP and settings for WhiteLabel? I will suggest you to kindly review this document - dpqi6EL7JaXixi2vtsExcjcFntqhcsZ7WmqJc7UY.pdf
Worth checking out Microsoft Learn for setting up the IDP and other configuration for SSO. enable-single-sign-on
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