If you experience any discrepancies with your task dates the most likely cause is a time zone or connectivity issue between Dooster and Google Calendar.

Are you or any of your users using the Google Calendar Sync feature?

Check these related articles:

https://dooster.net/wp/troubleshooting/completed-deleted-tasks-reappear/

and

https://dooster.net/wp/known-issues/completed-tasks-reappear/