BR-08
A rule of the European standard EN 16931 – applies to every invoice following the standard, including Peppol BIS Billing 3.0.
What this error means
BR-08
The seller details contain no postal address (BG-5).
How to fix it
Add cac:AccountingSupplierParty → cac:PostalAddress with city, postal code and cac:Country → cbc:IdentificationCode.