Get "access_denied for broker login oidc" in logs


My company is using Keycloak 10.0.2 on production environnement.
We have an “Identity Provider” that point to an Okta instance.
From time to time we get some errors in the logs : “access_denied for broker login oidc”.
I know that message is coming from :

I don’t know what to do to understand better the reason, I don’t even know if it’s related to Okta IDP.
I’m kind of stuck.
If you have any advice to understand better or to get more logs linked to this context, I’ll appreciate.