At present, the system does not support closing financial periods on a per‑ledger basis. This means that if a prior period needs to remain open for adjustments in the Nominal Ledger, the Purchase Ledger will also continue to default to that open period or depending on the document setting the financial year group default period.

Changing the below document setting to financial year default period and ensuring that the financial year default period is updated, it will always default to that setting. You can also turn off the amendable tick to stop users changing the period where you may have earlier ones still open.