c# – KSeF – send invoice

I’m sending new invoice in interactive mode.

After open session I using POST method

/api/v2/sessions/online/{sessionReferenceNumber}/invoices

Result is OK, but when I’m checking status using GET method

/api/v2/sessions/{sessionReferenceNumber}/invoices/{invoiceReferenceNumber}

I get status 430 and this information:

STATUS CODE: 430

STATUS DESC: Błąd weryfikacji pliku faktury

DETAIL: Rozmiar faktury nie zgadza się z zadeklarowaną wartością: '2491'.

Do you know what could be wrong?

This is C#

byte[] xmlBytes = await System.IO.File.ReadAllBytesAsync(path + "test.xml");
long invoiceSize = xmlBytes.Length; 

test.xml is accepted by KSeF “Wczytaj fakturę”