Im trying to create a new Print-Layout but im stuck at getting the Invoice ID.
The InvoiceNumber was originally in the Headsection of the Layout.
But iam using Custom Code in the Headsection so the Default
Sales Invoice
SINV-0002
gets overwritten
How do i get the Invoice ID as doc.naming_series gets me only the Series and doc.title gets me the Client the Invoice is issued to.