Hi @Code Bit · Thank you for reaching out.
Here is a sample: https://github.com/azure-ad-b2c/samples/tree/master/policies/force-password-reset-first-logon that you can refer to.
This sample demonstrates how to force user to reset password on the first logon. It is based on an extension attribute. When you create a B2C account via Graph API, you set this property to true. On run time, when user sign-in, Azure AD B2C checks the value of this extension attribute. If set to true, B2C asks the user to reset the password and removes this attributes from the user account.
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