To add a credit note product to an invoice, you can add a credit note product to a line item.

1. Open the applicable invoice.
2. Adjacent to Add new invoice line, select the plus button.
   
3. In the Product column of the new line item, select the credit note product.
   
4. Set the Quantity value of the new line item to -1.
   
5. Select Save.
   
   ezyVet shows a confirmation message:
   
   
6. If applicable, make sure that you complete the credit note allocation for the applicable invoices.
   Note: If you use Xero, make sure that you also do the applicable credit note allocation in Xero.