Create a document (or multiple documents if they should be generated according to the
same schedule) by using the Purchase invoices (AP301000) window.
Save each document
with the Balanced status. Do not release the them.
You can add supplier ledger
documents of the following types to schedules: Invoice,
Credit adjustment, Purchase credit note, and
Prepayment.
If you want to use a document that is already closed, copy, and paste it to a new
document.