Troubleshooting Order Sync Failure Due to Backordered Items
Most of the time, NetSuite will let an order have backordered items, and NetSuite Connector can sync the order without any issues. The exception is when you're syncing cash sales (usually for Amazon FBA and Point of Sale orders) and the item is lot-numbered. In this case, you'll see an error letting you know that to sync lot-numbered items on cash sales, you've got to have available inventory numbers in the right NetSuite location. Then, it shows the SKUs that don't have inventory numbers.
The items in this error can't sync because NetSuite needs a lot number on the inventory detail for them. NetSuite Connector doesn't have lot number information. NetSuite Connector has settings that automatically assign the first available lot to each item posted to sales and cash sales orders. When you turn on these settings, NetSuite Connector asks NetSuite for the first available lot number from the location being synced for the order item. But if NetSuite doesn't have inventory for that item in that location, there's no lot information available. So NetSuite Connector can't get the lot number from NetSuite to sync those items on the order.
To fix this error, you'll need to add inventory numbers for those items in NetSuite at the location used for the sync.