If you found a mistake in a closed payroll report, you can re-open the report to make corrections. Visit the Closed Payroll Reports page from the Reports section and look for the open 
icon in the far right column. Note that payroll reports can only be opened sequentially backward to avoid overtime calculation errors, so the re-open icon will only display for certain recent reports. After a report is opened, the icon will then appear for the next available report. When opening a payroll report, the report is deleted and must be re-closed after timesheets are edited.
Correcting for a Single User
If you need to correct payroll for only a single user, you can do so by first selecting an individual from the dropdown selector at the top of the Closed Payroll Reports page. The page will reload showing payroll reports segregated out for just that individual. When you click the re-open button, that person will be removed from the corresponding payroll report and their time will be put back on their timesheet. The existing payroll report, however, will remain.
After correcting individual timesheets, users removed from a payroll report can be added back into the original report by first selecting user(s) and then choosing the Append selected users to an existing payroll report option on the Close Payroll Period form.