PEPPOL-EN16931-R004
An official OpenPeppol BIS Billing 3.0 rule – checked for invoices sent over the Peppol network on top of the EN 16931 rules.
What this error means
PEPPOL-EN16931-R004
The specification identifier (CustomizationID) is not the exact Peppol BIS Billing 3.0 value.
How to fix it
Set it exactly (no extra spaces): urn:cen.eu:en16931:2017#compliant#urn:fdc:peppol.eu:2017:poacc:billing:3.0.