Univention Corporate Server: no renewal possible

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17

Seems to look good:

root@ucs:/etc/univention/letsencrypt# apachectl -S
VirtualHost configuration:
*:80                   is a NameVirtualHost
         default server ucs.kmvw-io.de (/etc/apache2/sites-enabled/000-default.conf:13)
         port 80 namevhost ucs.kmvw-io.de (/etc/apache2/sites-enabled/000-default.conf:13)
         port 80 namevhost ucs-sso.kmvw-io.de (/etc/apache2/sites-enabled/univention-saml.conf:63)
*:443                  is a NameVirtualHost
         default server ucs.kmvw-io.de (/etc/apache2/sites-enabled/default-ssl.conf:17)
         port 443 namevhost ucs.kmvw-io.de (/etc/apache2/sites-enabled/default-ssl.conf:17)
         port 443 namevhost dav.kmvw-io.de (/etc/apache2/sites-enabled/kdav.conf:2)
         port 443 namevhost kmvw-io.de (/etc/apache2/sites-enabled/univention-letsencrypt.conf:21)
         port 443 namevhost autodiscover.kmvw-io.de (/etc/apache2/sites-enabled/univention-letsencrypt.conf:42)
         port 443 namevhost autoconfig.kmvw-io.de (/etc/apache2/sites-enabled/univention-letsencrypt.conf:63)
         port 443 namevhost web.kmvw-io.de (/etc/apache2/sites-enabled/univention-letsencrypt.conf:84)
         port 443 namevhost ucs.kmvw-io.de (/etc/apache2/sites-enabled/univention-letsencrypt.conf:105)
         port 443 namevhost smtp.kmvw-io.de (/etc/apache2/sites-enabled/univention-letsencrypt.conf:126)
         port 443 namevhost mail.kmvw-io.de (/etc/apache2/sites-enabled/univention-letsencrypt.conf:147)
         port 443 namevhost ucs-sso.kmvw-io.de (/etc/apache2/sites-enabled/univention-saml.conf:38)
         port 443 namevhost web.kmvw-io.de (/etc/apache2/sites-enabled/web.kmvw-io.de.conf:3)
                 alias web.kmvw-io.de
ServerRoot: "/etc/apache2"
Main DocumentRoot: "/var/www/html"
Main ErrorLog: "/var/log/apache2/error.log"
Mutex default: dir="/var/run/apache2/" mechanism=default
Mutex mpm-accept: using_defaults
Mutex watchdog-callback: using_defaults
Mutex proxy-balancer-shm: using_defaults
Mutex rewrite-map: using_defaults
Mutex ssl-stapling-refresh: using_defaults
Mutex ssl-stapling: using_defaults
Mutex ldap-cache: using_defaults
Mutex proxy: using_defaults
Mutex ssl-cache: using_defaults
PidFile: "/var/run/apache2/apache2.pid"
Define: DUMP_VHOSTS
Define: DUMP_RUN_CFG
Define: ENABLE_USR_LIB_CGI_BIN
User: name="www-data" id=33
Group: name="www-data" id=33