As long as the invoice is only saved status, the invoice can be modified with the "Save" button at any time. If e.g. an invoice consists of too many lines of items, or we do not have accurate information for some items, the recording of the invoice can be suspended, the data already recorded will not be lost. The reason for this is that after saving, the invoice does not receive a serial number yet, so it does not qualify as an invoice, so it can be modified and edited at any time.