fatal UBL
[UBL-SR-49]-Value tax point date shall occur maximum once
/ubl:Invoice | /cn:CreditNote
(count(cac:InvoicePeriod/cbc:DescriptionCode) <=1)
Source: EN 16931-1 Schematron, UBL syntax binding (ConnectingEurope/eInvoicing-EN16931, EUPL-1.2).
Invoice XML (UBL 2.1 Invoice/CreditNote or UN/CEFACT CII D16B, max 5 MB):
Validate