If you have omitted an employee's termination date on a submitted FPS and you wish to correct this you will need to submit a second FPS with the dates. If you do not need to pay anything further to the employee:

Go to the employee record/s and open in Edit mode
On the Human Resources tab set the appropriate termination date
Save

Once you've fixed the employee data, do the following:

Create a new pay run
Change the Pay Run Type to "Adjustment"
Match the Period Start Date to the pay run you want to adjust
Match the Pay Date to pay run you want to adjust
Tick "Skip Pay Components"
Select only the employee/s you want to correct
Submit
Click "Return to Payrun"
Click Edit
Set the status of the pay run to "Payrun Paid"
Save
Click on the payslip in the sublist opening in Edit mode
Change the Payslip Status to "Paid"
Save (repeat 12, 13 and 14 for any other payslips in the run)
Initiate FPS
Edit the RTI Activity
Set the Late Reason to "H: Correction to Earlier Submission"
Save
Review and submit the FPS when happy

Useful Links

HMRC

https://www.gov.uk/running-payroll/fps-after-payday

Infinet Cloud

UK RTI Reporting

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