Source: linux – Why is my crontab not working, and how can I troubleshoot it? – Server Fault
Beware of sudo when running as a non-root user, crontab -e will open the user’s crontab, while sudo crontab -e will open the root user’s crontab. It’s not recommended to run sudo commands in a cron job, so if you’re trying to run a sudo command in a user’s cron, try moving that command to root’s cron and remove sudo from the command.