Validation rules

BR-CO-20

An invoice line period (BG-26) is present but carries neither a start date (BT-134) nor an end date (BT-135).

Rule: BR-CO-20 — official EN 16931 / XRechnung rule
Severity: error
Detected by: tier 3 — KoSIT validator (authoritative)
Reachability: Not expressible through the normbill invoice model — documented for completeness

The request schema rejects empty line periods via Zod refine.

How to fix it

Fill the line period's start_date and/or end_date, or omit period.

BR-CO-20 auf Deutsch — was bedeutet der Fehler?

Ein Positionszeitraum (BG-26) ist vorhanden, enthält aber weder Startdatum (BT-134) noch Enddatum (BT-135).

So beheben Sie den Fehler

Füllen Sie cbc:StartDate und/oder cbc:EndDate im Zeitraum der Position — oder entfernen Sie ihn.

Official sources

Every 422 from the API lists the rule id, the path in your request JSON, a plain-language message and a suggested fix — see the docs overview for the report format.

Or try it live: drop any XRechnung XML on the free validator — same KoSIT-backed report, no account.