Once, the Freight invoice is generated from the Freight bill details form; it's possible to click again on Generate freight bill and it's re-created for the total amount including all transactions
System allows to generate another freight invoice even if all the freight bill lines have been already fully included in a separate freight invoice.
Expected result: If the freight bill line has been already included in the freight bill invoice, inclusion of the same line should not be allowed in the another invoice. In case Partial invoice feature is developed in the application, when clicking on Generate freight bill, only the remaining amount should be added in the created record.