Hello @Preston Checkan , the error you're facing is caused by the lack of the client_id
query parameter in your authentication URL. Ensure your application configuration contains the required values for the aforementioned and other required parameters. Take a look to this document for how to configure an ASP.NET Core application.
If you're using Azure Web Apps please take a look to Configure an App Service app.
For more information about error codes take a look to Error codes: Azure Active Directory B2C.
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