As you can see, the server replies with 404 Not Found to a PROPFIND request on PROPFIND https://10.168.178.155:443/card.php/addressbooks/firsttestaccount/default/. This means that either there is no addressbook at this URL (is the URL correct?), or there is a server problem.
Why do I get a “calendar-proxy” response to a contact sync request???
That’s a good question, but I guess you will get more competent support in a Baïkal forum, as this seems to be a server problem.