The tax amount due in a given payroll period can be amended from the Payroll Calculations screen. To amend the tax amount in a calculation, select the employee from the Payroll Calculations screen.
In the Payslip section, click the Edit icon, next to Tax as highlighted in the screenshot below (Note: The payroll must be unfinalised before making any amendments).
In the Tax window, click the "Edit" icon and enter the tax amount in the Tax amt. field. If necessary, enter any remarks in the Remarks section.
Save to apply changes.