How do i deal with the following message, so that i can file the vat? you must also click save again to make this change that is prior to the closing date.

Thank you reaching out to the Community, @gergoviewines.

I can get this fixed for you in no time. It usually happens when you set your books to close on a specific date in QuickBooks Online.

To file the VAT, I suggest going to the Account and Settings section and make changes. You'll need to untick the box for closing the books.
 

Here's how:

1. Click the Gear icon in the upper-right corner.
2. Below Your Company, select Account and Settings.
3. Go to the Advanced tab.
4. Under Accounting, remove the checkmark on the box beside Close the books.
5. Hit Save, then press Done. 

Meanwhile, I've attached some articles you can use to close or edit your books in QuickBooks:

• Close your books to lock past transactions.
• Edit your closed books.

Let me know in the comment section below if you have any other questions. Have a great day ahead.