Hello and welcome to the QuickBooks Community, Jane
We'll be happy to assist you with processing the payroll for your leaver.
As a first step, we recommend using HMRC's PAYE calculator to calculate the taxes and amount due. The figures can be used as comparison as they should match the amounts in QuickBooks exactly.
If you need to make amendments to a submitted payroll, you can roll back the payroll in QuickBooks Online. Once the necessary changes have been made, you can then re-run the pay period and re-submit this to HMRC (as option H - correction to earlier submission). This option overwrites the data HMRC received for the period, making sure that it isn't duplicated.
If you would like a helping hand, please contact our support team directly on 0808 234 5337 or by chat messaging. The agents available here will have access to set up a remote screen share using secure software where they can guide you through the process.
Thanks for reaching Intuit QuickBooks for support on the Community today. Have a great day!