apache2.service: Failed to set up mount namespacing: Permission denied

the solution without nesting:
https://stackoverflow.com/questions/55728957/apache-failed-at-step-namespace
https://help.directadmin.com/item.php?id=614

$ sudo sed -i -e ‘s,PrivateTmp=true,PrivateTmp=false\nNoNewPrivileges=yes,g’ /lib/systemd/system/apache2.service
$ sudo systemctl daemon-reload
$ sudo systemctl start apache2.service
$ sudo systemctl status apache2.service