Hello @Termindiego25 !
As your Passbolt instance is not in debugging mode, it doesn’t show further details. You might need to see your server logs to grasp more details.
However, I think I know where it could come. The OpenId Configuration Path shouldn’t be an absolute URL (AFAIK) but rather a relative one.
So, I think, you probably need to put /.well-known/openid-configuration only in this field.
Hope it fixes your issue.