I develop a console application to add item to a SharePoint List associated with a nintex workflow.

When the console application add an item, the workflow starts and create a task to approver . then the approver approve or reject the task, the task seems still in waiting status. I check the workflow task, the approvalComment is updated but percentComplete not. 

if I start the workflow manual, the workflow works well.

If I fill NewForm.aspx(SharePoint default UI), the workflow works well.

If the workflow works well once, the automatically works also after 

it is a interesting thing, is there anyone could tell me what happens?

thanks and best regards

JD