If no items appear in the list, you will need to add your items. (For instructions on how to add items in Seller Central Help > Inventory > Add a Product).
When you convert listings, you are prompted to choose one of three options:
For help on adding products to shipments or creating new shipments, see Merchant Manual section 5.0 Shipping Inventory to Amazon.
When you convert a product that you fulfil to one that Amazon fulfils, the listing is removed from the website until inventory is received by an Amazon fulfilment centre.
If you receive this message while converting your listing to 'Fulfilled by Amazon', then you have added a product with a Merchant SKU that is a duplicate for an item currently in the FBA inventory. Our fulfilment centres will be unable to fulfil current inventory, to process items that are returned by customers or to receive any inbound items as a result of the duplicate Merchant SKU.
"Item Exception: 1 of 1 selected item for this request requires your attention."
You have two options.
Option 1: If you entered a duplicate Merchant SKU by mistake, you will need to return to the All Inventory View page and do the following:
Option 2: If you intended to use a duplicate Merchant SKU to replace existing listings, you will need to contact a technical account manager by going to Seller Central Help > Contact Amazon > Contact Us and using the Contact Us form under Technical Support. Ask for help to deactivate the old item and convert the new item to Fulfilled by Amazon.