Action button is not displaying in approval Notification for Job Requisition

Summary

when Enabled Auto Claim in BPM for Job Requisition approval, Action button is not displaying in Approval notification workflow

Content

Below is client requirement w.r.t approval workflow, 

1. They want Claim button in the Job Requisition approval notification workflow
2. Approval should be able to add Assignee into the Job Requisition approval workflow

I have Enabled Auto Claim in BPM  and in Approval Rule I have selected participant type as Single. with this config Claim button is displaying in approval notification but the Action button is not displaying.  

Please Advise why the Action button is not displaying.