Web Blocking Log

Hi,
where can I see the log-file of the Web Blocking feature to drill down issues?
Using a browser to open a blocked site shows the Balance router’s block page - so no problem.
Problem starts if an iOS app can‘t connect, so you do not see why it is blocked.
Just discovered by luck, that sso.guj.de (a login page of German newspaper „Capital“) is blocked by mistake by the „Porn“-Web blocking filter…