That is wrong it should be
drwxr-xr-x 18 www-data root
chown www-data:root /var/cache/nginx/micro/$domain
chmod 640 /var/cache/nginx/micro/$domain
should solve the issue
That is wrong it should be
drwxr-xr-x 18 www-data root
chown www-data:root /var/cache/nginx/micro/$domain
chmod 640 /var/cache/nginx/micro/$domain
should solve the issue