field1 rules
Every EN 16931, Peppol and XRechnung rule that constrains BT-12. If one of them fails, the others are usually worth a look — a wrong value in one field tends to break several checks at once.
| BR-DE-CVD-01 | fatal | Das Element "Contract reference" (BT-12) muss übermittelt werden. |
Nothing is stored, and the whole invoice is checked, not just this rule. A PDF only works if it is Factur-X / ZUGFeRD — a PDF with the invoice XML inside it.