I am getting the same alert notification every hour in 2Do v3 for the same task
Article ID: 644 | Last Updated: Wed, Oct 15, 2014 at 9:25 AM
That is a new ’Nag’ feature in 2Do, switched ON by default. To turn it off, please go to Settings > Notifications > Nag Me
2Do can optionally nag you for the alert every minute, hour or day.