Quantity invoiced does not match Quantity fulfilled

We can solve the problem of “manually creating an invoice for a sales order, it adds the entire SO quantity, not the shipped quantity” using the standard way of NetSuite

Go through the Navigation Setup -> Accounting -> Accounting Preference

Uncheck the “Show Unfulfilled Items on Invoices “ and “Invoice in Advance of Fulfillment “checkboxes of the invoicing preference on the Order Management subtab of the Accounting Preferences

Invoice in Advance of Fulfillment = False, and Show Unfulfilled Items on Invoices = False

1. When the Sales Order is billed, only the Shipped items can be Invoiced.
2. When the Item Fulfillment is billed, only the items Fulfilled/Shipped can be Invoiced.