My Inbox release is not working for Purchase Requisition

Hi Experts,

We are just installed SAP FIORI, we have followed the steps from configuration document. The front end web displays the manager's inbox with all the approval emails.

We are currently on ECC Ehp 7 as our backend system.

When we click on the approve button nothing happens. Kindly advise on how to proceed on this issue. Please see the screen shot below: