Does anybody have any issues with Tasks duplicating or showing up again after it has been marked complete?
I’m having the same issue. When I look at My Tasks I will see current tasks (not yet due) show up multiple times and previous completed tasks show up as not done even though I marked them done.
I am having the same problem, what did you do?
I still have it. I did go in and delete a bunch of them; I also tried deleting all future tasks as well as what I thought was the original task. I got so tired of doing this I have given up on fixing it. I just stopped using Sub Tasks as this seems to be the culprit.
Sorry, I don’t have better advice or a fix 
I’m experiencing the same issue.
We are having the exact same thing happen… we mark a task complete, and it shows complete on the device that marked it, but other people show it as still open. Then it randomly later marks complete and duplicates itself with a new identical copy that is NOT marked complete, and with a new due date of like a week later! Deleting the duplicates so far seems to be our only fix. We are using Windows 10 desktops with Chrome, Android app, and IOS app. Could this be an IOS app induced bug (the IOS app person just came onboard yesterday, and the problems seem to have then started shortly after)?