If you have resigned an employee but still see the resigned employee on the Run Payroll page and you wish to remove him from the calculation. There are 2 ways to do it:
On the left panel of your admin dashboard, head to Payroll > Run Payroll. You can click "Refresh Payroll". This action would reflect the latest information about the employees, especially when there are changes such as employee termination, salary adjustment, contribution adjustment, etc.
However, this would clear all changes made including all added pay items and deductions in the current month's payroll.
On the left panel of your admin dashboard, head to Payroll > Run Payroll.
If you do not wish to wipe out the input you have added in the current month's payroll but still want the resigned employee to be removed from the payroll calculation, you can untick the resigned employee's name then click Run Payroll.
Once you have unticked and clicked Run Payroll, you will not see the resigned employee in the list anymore in the Payroll Summary page.