How to re-apply a report template to an existing report
Navigate to your main Reports control panel using the "Reports" option from the root of your account.
Tick the box(es) next to the report(s) where you'd like to reapply a template.
Click "Apply Template" at the top of the column.
Choose the template to apply, then click "Apply Template"
The template will then overwrite the existing contents of the report.
Note: Please use caution. Once overwritten, the previous contents of a report cannot be recovered.