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 is recommended.

Payment Payment on invoice failed with the following errors:

Invoice could not be found

The invoice the payment is applied to has not been successfully imported into Xero yet.Ensure that all invoices have been sent from WorkGuru to Xero successfully.
Payments can only be made against Authorised documents
The invoice the payment is applied to has been imported but not approved in Xero.Approve the invoice in Xero
Payment amount exceeds the amount outstanding on this documentThe payment total does not match the total of the invoice.Edit the invoice to match the total.  Void the invoice in Xero, mark as unsent, then delete the invoice WorkGuru. Reissue the Invoice and re-apply the payment.
Additional people cannot be added when the primary person has no email address set.Client has an email address against its contact but not the Client itself.Edit the client to enter an address on client email field as well as the contact.
Purchase Order failed with the following errors:  Could not find purchase order number x | in returned list.The PO has been received without a Supplier Invoice Number enteredOn the received PO, click Update Invoice Details and enter a Supplier Invoice Number and re-import to Xero.
Journal StockMovement failed with the following errors: Couldn't send the journal to Xero for "mm/dd/yyyy hh:mm:ss". Please check your lock periods and try again.
The period/s in Xero have been locked for editing.
Edit your locking periods in Xero to ensure the periods being sent are not locked.
Xero API error calling CreateTimesheet:{"...", "Message" : "TrackingItemID is required for each timesheet line.", "..." }
Xero tracking categories have been set up to track timesheets.
Disable tracking categories being applied to timesheets in Xero. WorkGuru does not support tracking categories on timesheets.
XX failed with the following errors: {"Type":null;"Title":"Unauthorized","Status":
401,"Detail":"TokenExpired: token expired at mm/dd/yyyy hh:mm:ss", ...}
The token used to authorise WorkGuru against your Xero account has expired.
Log out and back in to WorkGuru. If issue persists, disconnect and reconnect to Xero from the Xero page. Note: you will need advisor-level access in Xero to reconnect.