The class Kolab2FA\Log\Syslog cannot be found on /usr/share/roundcubemail/plugins/kolab_2fa/lib/Kolab2FA/Storage/Base.php line 72.
No directory plugins/kolab_2fa/lib/Kolab2FA/Log/ exists in the source code management repository rRPK. No reference to a logging library exists in the plugins/kolab_2fa/composer.json file.