motion install on raspberry pi Raspberry Pi Model B Rev 2: logging issue; howto solve?

Hello,
since my raspberry SD boot card was dead, I am reinstalling raspbian on it for making running the home observation video again.
So far achieved:
- raspberry reachable via ssh
- motion installed

uname -r
Code:5.10.63+parameter in /etc/motion/motion.conf
..
log_file /var/log/motion/motion.log
..

now..
sudo service motion restart
Code:Message from syslogd@raspcamera at Nov 23 21:29:02 ...
motion[928]: [0:motion] [EMG] [ALL] motion_startup: Exit motion, cannot create log file /var/log/motion/motion.log: Permission denied

Broadcast message from systemd-journald@raspcamera (Tue 2021-11-23 21:29:02 CET):

motion[928]: [0:motion] [EMG] [ALL] motion_startup: Exit motion, cannot create log file /var/log/motion/motion.log: Permission deniedfollowing did not help:
(file created with
sudo mkdir motion
sudo chown root:motion motion
sudo touch /var/log/motion/motion.log
sudo chown root:motion /var/log/motion/motion.log
)

sudo chmod 666 /var/log/motion/motion.log
sudo ls -l /var/log/motion/motion.log
Code:-rw-rw-rw- 1 root motion 0 23. Nov 21:19 /var/log/motion/motion.logAny suggestion/advice/comment is welcome.