You can manually delete a report that’s completed or still in progress. Reports are automatically deleted 90 days after they’re generated.
If the report was created using a template, then deleting the report doesn’t delete the template used to create it and therefore doesn’t affect any future report instances that are scheduled. To delete a report schedule, delete the report template.
In the main menu, click Search > Insights & Reports > Reports, which opens to the Latest Reports tab.
Select the check box next to each report you want to delete.
Click Delete.
In the confirmation message, click Yes.