Back Office—->Orders—>Statuses—>Preparation in Progress(Or any status which is set as default), I unchecked “Show Delivery PDF.”
Status should not have “delivered” option.
In table ps_order_history remove this order’s “Delivered” state
(Not sure if necessary, should test)
In tables ps_orders/ps_order_invoice
delivery_number change to 0
delivery_date change to 0000-00-00 00:00:00