Hello Mike Palgon,
To customize the "User Details" string in your Azure AD B2C Password Reset user flow. User Details could be part of the "self-asserted" page or a more general template for your flow. You'll need to check Self-asserted UI elements, as this is where Azure AD B2C will often show text like "User Details."
For password reset flow, you need to edit the page layout version according to the self-asserted element Page layout versions
Customize the user interface with HTML templates.
There is a document which will help you with your requirement do check: https://github.com/azure-ad-b2c/html-templates/blob/main/templates/AzureBlue/selfAsserted.html
I hope this clarifies things.
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