Hi @Hetul Patel ,
Thanks for reaching out.
To get the exception from Rest API, you need to call your REST API as a validation technical profile as part of a self asserted technical profile.
The validation technical profile returns returns 4xx HTTP status code and can be presented to the screen, as there is a page being rendered.
<TechnicalProfile Id="LocalAccountSignUpWithLogonEmail">
<ValidationTechnicalProfiles>
<ValidationTechnicalProfile ReferenceId="AAD-UserWriteUsingLogonEmail" />
**<ValidationTechnicalProfile ReferenceId="REST-API" />**
</ValidationTechnicalProfiles>
<UseTechnicalProfileForSessionManagement ReferenceId="SM-AAD" />
</TechnicalProfile>
Generally, when your API sends an error response to AAD B2C, it will halt the execution of the journey, but with validation technical profile you can handle this behavior using ContinueOnError.
hope this will help.
Thanks,
Shweta
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