To re-authorize your Xero account you will need to login to your PaySync account and navigate to Settings > Payroll or select Fix Now in red on the dashboard under Payroll.

Once you're looking at Payroll Settings you will need to click on the Application header then you will see the Authorize Now button in green.

Clicking the Green Authorize now button will take you to a Xero login page which you will need the correct Xero login account that has access to all items involving payroll to authorize properly.

Once you've logged in and selected your Xero accounts and it shows them in Paysync again with a green tick you will be able to sync data between Paysync and Xero again.

This solution is referencing the Aussie Time Sheets - PaySync Software, for more information please visit: