It seems like you are encountering an error page when testing your sign-in/sign-up user flow in Azure AD B2C. This could be due to a variety of reasons, such as incorrect configuration or missing policies. One common error is the "AADB2C90118" error, which occurs when the user enters incorrect credentials. You can check the Azure AD B2C troubleshooting guide for more information on how to handle common errors.
Additionally, you can try testing your user flow with different browsers or in private browsing mode to see if the issue persists. Make sure that you have followed all the necessary steps for setting up your user flow, as outlined in the Azure AD B2C documentation.
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