I ran into the exact same problem. However, I felt duped when I read what Trevor778 wrote in this post:
I had the same problem – the task worked but the status kept showing Running. One simple thing to try is click on the Task Scheduler Library in the left column. Click Action/Refresh. Presto. Status changed to Ready. That’s all it was for me, the task ran fine, just the status didn’t update. Hope this helps.
ref: https://social.technet.microsoft.com/Forums/en-US/2f6dc29c-3b8b-45f5-a2a7-53e076acc062/task-scheduler-scheduler-status-is-being-running-always?forum=winservergen