3590108 - Logon URL under IAS - 'Allow users stored in Identity Authentication service to log on' Return Error

• The Identity Authentication Service (IAS) application is set up to use the corporate IdP as Default, but the 'Allow users stored in Identity Authentication service to log on' setting is not functioning as expected.
• The expectation is that users can access the application with their Identity Authentication credentials. However, upon invoking the logon URL and entering credentials into the login screen, a HTTP Status 400 or "Where to" is received.

Identity Authentication Service

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