Approval Notification is not triggering from BPM Worklist

Summary: We have defined simple condition , say Change Priority == "High".

Updated the approval group. Added the approval group.

Rule Base is checked in workflow status condition

Notifiation is not triggers for approvers. Fyi notification is triggering when Change Assignee is assigned to workflow.

When i go manually to notification and click on "Created by me" i can see notification but assigned to field is empty.

When i manually add user in workflow, Approval notification is triggering.

I can take "Approval" action when i manually open notification. Post approval, i get bell notification.

I am trying to figureout the issues.

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