If your are asked to confirm that you have read a post or that you participate in an event, you will find it on the page "Awaiting reply".
Posts awaiting your reply
This is where you find posts where the author has asked for “Read confirmation” or “Confirm participation”.
Awaiting confirmation - All posts where the author has asked for “Read confirmation” will remain in this tab until they have been confirmed. All posts where the author has asked the recipients to confirm participation will remain in this tab until they have been accepted or declined.
Answered - Once Users have confirmed read on a post or their participation in an activity the post will move to the “answered” tab.