Follow these instructions to clear an alert acknowledgment from the Alerts page.
To clear an alert acknowledgment from the Alerts page:
Click Alerts from the Dashboard menu to access the Alerts page.
In the Alerts Table, locate the single alert you want to acknowledge.
Click the Options icon associated with the alert.
Select Unacknowledged.
When you clear acknowledgment for an alert, the Alerts page will automatically refresh and modify the alert's Acknowledged field. The contents in the Acknowledged By and Acknowledged Date/Time fields will also clear. Notes recorded in the comments field are retained.