Hi Sergey,
Thank you for posting your query on Microsoft Q&A. I am Saiteja from Q&A will be assisting you with your query.
Based on your query, here is my understanding: Would like to achieve password reset along with Signup and Sign in which you are facing the issue. I would like to suggest the official document here.
This document helps in configuring forget password with all the required steps which includes claims provider update, user journeys.
The sign in validation errors can be configured in localization by following this starter pack.
I hope this information is helpful. Please feel free to reach out if you have any further questions.
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