Message

Specification identifier MUST have the value 'urn:cen.eu:en16931:2017#compliant#urn:fdc:peppol.eu:2017:poacc:billing:3.0'.

Context
ubl-creditnote:CreditNote | ubl-invoice:Invoice
Test
starts-with(normalize-space(cbc:CustomizationID/text()), 'urn:cen.eu:en16931:2017#compliant#urn:fdc:peppol.eu:2017:poacc:billing:3.0')
Usage
/ ubl:Invoice / cbc:CustomizationID