Update an Invoice after submitting VAT return

Hello,
I found here in QuickFile I can not change the invoice and credit note after submitting VAT return.
In this case will the new additional Invoice be the best option to proceed or I can still update an existing one with some tools?

It depends what you want to change - if it’s just which nominal code you assigned it to then you can do that from the chart of accounts with the “move to new code” option but anything else, and particularly anything that will change the amounts, dates, or net/vat breakdown, would have to be done through credit notes and/or additional invoices.

As a general rule you should never really be making any changes to any VAT invoice or credit note once you have sent it to a customer, since they may already have used the original version to claim their own purchase VAT. I would always issue credits and new invoices in such a case, rather than making changes to an existing invoice number. The “move to new code” is the only exception since that doesn’t appear on the customer’s document, it’s only for your internal book keeping.

@ian_roberts thanks for explanation and your thoughts, we think same so will issue an additional invoice