You need to extend the employee's last pay date to allow payroll processing after his termination date, then process a dummy payroll. You will only be able to process an A8B once the dummy pay record is generated. Please follow the steps below to do this:
Process dummy payroll
Go to the Payroll module, and click Pay Details.
Find the Employee and change the Last Pay Date to the current period pay month. (eg. Jan 2026)
Click Save, click Pay Record, and click New.
Double-click Year (change to year 2025), select any period.
Click Confirm, and click Next to process the employee's Pay Record.
Process Appendix 8B
Go to Income Tax Module, click Process, Income Tax.
Click Proceed From Steps 1.