Xero API Message
CauseResolution
The TaxType code 'OUTPUT' cannot be used with account code 'x'.
Tax on a line item on that PO is configured as a sales tax code, not a purchase code.  Usually "GST on Income" instead of "GST on Expenses"
From the PO's details page in WorkGuru, click Update Invoice Details and update the tax name setting to the correct tax (usually GST on Expenses)
The quantity value '-x.0000' is invalid. Quantity must not be less than zero.
Xero does not accept negative values on PO or Invoices
Create purchase credits directly in Xero and adjust stock accordingly via a stock adjustment in WorkGuru if required.
Invoice not of valid status for modification
The PO or Invoice has already been sent to XeroConfirm the PO is in Xero for the same value as WorkGuru.  Open the PO's detail page in Workguru and click Mark as Sent to remove it from the list to send to Xero.
This document cannot be edited as it has a payment or credit note allocated to it.
The PO or Invoice has already been imported into Xero, marked approved and has a payment recorded against it.Confirm the PO is in Xero for the same value as WorkGuru.  Open the PO's detail page in Workguru and click Mark as Sent to remove it from the list to send to Xero.
Another contact has this contact number. Please enter a different contact number.
More than one contact in Xero has the same phone number
Edit the contacts in either Xero or WorkGuru to ensure only every client and/or contact has a unique phone number.  If they are legitimately the same, using the area code to make one unique isrecommended.