Can't figure out how to link alexa smart home account to user in keycloak

Question

I have set up account linking in the alexa console and are pointing these urls to my keycloak instance:

The name of my realm is external

Auth uri: https://myhost.com/realms/external/protocol/openid-connect/auth

Token uri: https://myhost.com/realms/external/protocol/openid-connect/token

and when linking my skill, I get the login page from keycloak. When I type in the username/password of my user, I get "Invalid username or password" and I see this in the log on keycloak:

2024-03-26 10:54:25,858 WARN [org.keycloak.events] (executor-thread-84) type="LOGIN_ERROR", realmId="6bfb3b0a-0a2b-4533-86d0-ad9beb9079fb", clientId="alexa", userId="null", ipAddress="192.168.0.1", error="user_not_found", auth_method="openid-connect", auth_type="code", redirect_uri="https://pitangui.amazon.com/api/skill/link/MIOLQ41NH0GM1", code_id="c835d795-f699-4f26-bcc2-bb47222f0529"

The id of the realm matches the external realm

The user I log in with is created by a user interface using another client than the one I use for my alexa skill.

This is the config for the client: Capability config

Does anybody have any pointers on where I'm missing some setup or where I might have a misconfiguration?

I tried doing account linking using the alexa app and I expected the keycloak to authenticate when requesting it using my client for alexa.

I got "Invalid username or password" in the login page.

I tried the same with a google home action and got the same result

Answer 1

I think it has to do with running it though an ngrok tunnel. Just tried it out on fly.io and it worked like a breeze