Leave Request for Approval not appearing in POWL Inbox

Hi experts,

I'm still a newbie in POWL and just followed this guide POWL Inbox configurations for Manager Self-Service EhP5 and above for Approving Leave Requests. My problem is when the approver checks his Inbox, Leave Approval count shows correctly in Active Queries but nothing in his inbox as shown below:

But when I check RPTARQAPP in SE38, all requests that need approval are there.

I'm not sure if I missed something. Need your expertise on this.

Thank you very much,

Howell