Hi @Jairo Ortiz ,
Thanks for reaching out.
Are you using the startup pack https://learn.microsoft.com/en-us/azure/active-directory-b2c/tutorial-create-user-flows?pivots=b2c-custom-policy#get-the-starter-pack provided by Azure AD B2C?
Make sure, in the B2C tenant, you provide the API permission to ProxyIdentityExperienceFramework app. If this permission is not added, sign-up works but sign-in fails.
Also, double check if ProxyIdentityExperienceFrameworkAppId and IdentityExperienceFrameworkAppId are added to the login-NonInteractive technical profile, as mentioned and not vise-versa by mistake.
Adding signing and encryption key would help in issuing the token.
Make sure you add both the keys as described in document in the policy keys
which is used in base file of startup pack in multiple technical profiles (JWT issuer, AAD-common)) which are calling while user journey to get the token.
In case the above does not work for you, please send us an email on azcommunity [at] microsoft [dot] com referencing this issue with a subject line "ATTN:shweta" to help you further.
Hope this will help.
Thanks,
Shweta
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