SharePoint Approved and Rejected buttons not appearing in task form in Visual Studio workflow

Recently we were working in a visual studio 2015 workflow for SharePoint online sites. The workflow we have developed as a SharePoint hosted add-in. In that workflow, we have added a custom task content type which was inherited from the Workflow Task (SharePoint 2013) parent content type.

After the workflow deployment, we were checking to approve or reject few tasks. But we noticed the Approved and Rejected buttons are not appearing in the Edit task form. So we were not able to approve or reject the tasks. We can only see Save and Cancel button like below:

Solution:
When we do an analysis we found out that, for one of our requirement we were making the “% Complete” column as hidden. Ideally it is advised that “% Complete” and “Task Status” columns should not be hidden. So we make the “% Complete” column as Optional like below:

After this we were able to see the “Approve” and “Reject” button properly like below:

You may like following SharePoint workflow tutorials:

• SharePoint Online Video: Deploy SharePoint Designer Workflow into Production
• SharePoint designer workflow examples Create workflow using SharePoint designer 2013 video tutorial
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• How to Trigger Sharepoint 2013 Designer workflow on a list item by calling REST API using jQuery?
• Impersonation step missing in SharePoint 2013 Workflow
• How to hide approve reject workflow approval button from ribbon in SharePoint online using CSS?
• How to send email in visual studio 2015 workflow in SharePoint hosted add-in in SharePoint online?
• Retrieve site workflow id using JavaScript Object model in SharePoint Online

Hopefully, this post may be helpful to solve SharePoint workflow task form approve reject button not appearing issue.