If a pay has been processed incorrectly it is normally best to delete the appropriate previous. To do this select the employee in the main payroll screen (you may have to change dates if not appearing), then select Edit form the left menu to bring up the Payroll Edit screen. Then we can edit the details but we have to ensure the related tables are also updated. You would normally use the following procedure:
Provisionally enter the correct amounts in the Payroll Edit screen to get the correct figures
In the History grid below change the Gross, Tax and Super figures as required. Do not change the year to date figures as these will update automatically.
Then select Accounts, Purchases and find the Payroll purchase transaction.