Validation rules

BR-31

A document-level allowance (BG-20) has no allowance amount (BT-92).

Rule: BR-31 — official EN 16931 / XRechnung rule
Severity: error
Business term: BT-92 — Document allowance amount
Field in your JSON: invoice.allowances[*].amount
Detected by: tier 3 — KoSIT validator (authoritative)
Reachability: Only reachable when validating your own XML — normbill-generated documents cannot trigger it

The request schema requires amount (or base_amount + percent) on every allowance and the serializer always writes cbc:Amount; the UBL schema makes the element mandatory too, so the XSD tier reports hand-built XML without it first.

How to fix it

Add cbc:Amount to the allowance.

BR-31 auf Deutsch — was bedeutet der Fehler?

Ein Nachlass auf Dokumentebene (BG-20) hat keinen Nachlassbetrag (BT-92).

So beheben Sie den Fehler

Ergänzen Sie cbc:Amount im Nachlass.

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.