I have set up a cronjob for root user in ubuntu environment as follows by typing crontab -e
crontab -e
34 11 * * * sh /srv/www/live/CronJobs/daily.sh 0
It might also be a timezone problem.
Cron uses the local time.
Run the command timedatectl to see the machine time and make sure that your crontab is in this same timezone.
timedatectl