BR-CO-21 — E-Invoice Validation Rule & Fix

Fixture ID: allowanceEmpty · XPath: /ubl:Invoice/cac:AllowanceCharge[1]/cbc:AllowanceChargeReasonCode

1. Why This Rule Triggers (Diagnostic Message)

Taken individually, the reason (BT-97) and the reason code (BT-98) on the document level allowance at allowances[0] are both optional terms — which is why this constraint exists separately from BR-33: it is the co-occurrence rule that forbids the one combination the cardinalities allow, namely neither. Supplying both is explicitly permitted and is usually the better answer, since the code is what a receiving system can act on automatically and the text is what a person reads.

2. How to Fix BR-CO-21

Add allowances[0].reason, allowances[0].reasonCode, or both. If no UNCL 5189 code fits what you are discounting, omit the code and write the reason as free text — the list has no "other" entry, and inventing a code fails BR-CL-19.

3. Valid Code / Payload Example

"reason": "Discount", "reasonCode": "95"