Issue
So the scnaerio s like the after creating a sales order user adds a new item to the sales order and then when he created the invoice, he had not selected the item from the sales order that is automatically auto populated. instead, the user manually enters the same item as a new line in the invoice so in this case when the invoice is saved the client was expecting the sales order to be billed as well but still the sales order show as partially fulfilled you need to know what the reason is for the same.
Solution
The reason for this issue is like instead of directly having the item populated from sales order to invoice if we add the same item manually to an invoice there won’t be a link for that item with respect to sales order. for every sales order item if you transform it to an invoice there will be a related order line ID so that is how NetSuite determines that the sales order line has been successfully invoiced but in this case since the user manually adds the item to sales order that is the reason why there is no relation between the sales order item and the same item which exists in the invoice so to handle this case we need to manually edit the invoice remove the manually added line item and then from the sales order we need to transform it again so that the new items automatically comes in sales order then save the invoice in this way the filter will be completely billed.