I just copied the configuration file that you sent and there are some errors in here:
root@didkamailio:/etc/kamailio# /etc/init.d/kamailio start
[....] Starting kamailio (via systemctl): kamailio.serviceJob for kamailio.service failed. See 'systemctl status kamailio.service' and 'journalctl -xn' for details.
failed!
I think configuration file contains wrong things.
Regards.