In the event that an item on an order must be changed to a different product for damaged product replacement, incorrect stock etc., you must use the Change Item tool within the Item Quick Actions toolbar in Marketplace Customer Service. To begin, find the affected item(s)/order using the search tool in Marketplace Customer Service.
After clicking that button there will be a search box that pops up prompting you to find the desired item for the change. Simply search for the item and click the condition configuration (New or Used). A confirmation box will pop up. Clicking 'ok' finalizes the change. The order will now have a row for the original item with an Item Status of Cancelled, and a new row for the new item.
*NOTE* Changing the item on the order will not automatically change the order price; the system transfers the original amount to the new item. If the new item costs more or less, you will have to make the appropriate adjustments in the item information area. This makes it easy to track the balance of the customer's order.