In the Fulfill Items popup, these fields are required:
After you fill in the final information about the shipment, saving the fulfillment information prompts auto-invoicing and the information is no longer editable. The amount that's invoiced is determined by the final quantities and shipping costs that you enter.
These fields are optional, but the more information you include, the more seamless the process will be with your customer:
Important: After you save a fulfillment, it is not editable.
To indicate that you have fulfilled the last set of units for an order item, use the Final fulfillment field. This is required for payment because it lets the system know if there is any overproduction or underproduction.
Once you've created a fulfillment, a "Mark delivered" button will appear. Click this button to mark that the shipment is delivered and upload the "Proof of delivery". This will trigger any final invoices that depend on shipping charges, and have payment terms that are due on delivery.