Notification not disappears when approver take action approve or reject

Summary:

when approver take action from email or from application to a purchase order approve or reject the action taken but the notification list still as is and the document action not removed from list. because of that approver couldn't differentiate between what need action and what not need. any advice ?

Content (required):

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):