Website backup only runs sometime

Hi,
On a website running on ISPConfig I see that, even If backups are configured daily, it only run every 3 or 4 days. I enabled the debug Loglevel but neither cron.log or ispconfig.log are showing anything about this, how can I find out what's happening?

Thanks

 

Any help?

 

Is it set to /var/backup? Or did you change the location?
And is it running as root?

 

Hi, thanks for your reply. Yes it's on /var/backup and it's running as root.