Delete Scheduled Backup Plesk

[mdde]

Hi,
i have set a new Date + Time for Backup for external FTP Server.
Now i backups twice as if it hasn't deleted my old plan.

What can i do? i wann to kill that Scheduled Backup Plan in the Night at 3 o Clock, as i switched it to 11 o Clock...

I have Plesk 12.5 and Debian 8.x