The invoice number is missing
Every invoice must carry a unique identifier (BT-1).
Only the issuer holds this value: Factlint reports it and never fabricates it. Test your invoice to find out whether it is affected.
The message your validator prints
Copied verbatim from the sealed artefact: this is the exact sentence the check prints when this rule fails.
[BR-02]-An Invoice shall have an Invoice number (BT-1).
Quoted from schematron-cen 1.3.16, licensed under EUPL-1.2.
Common searches around this code
These phrases mirror what an integrator searches for: code, syntax, rule, business field and correction.
Test your file with this error in mind
Upload the invoice involved: the report will say whether this code appears, where it appears in the document, and whether Factlint can only report it or also fix it.
To automate this check in an ERP flow, call the validation API and link every returned code to its public page.
Why this error happens
The invoice number belongs to the issuer's own numbering: sequential, without gaps, and binding on their accounts. Nothing in the document makes it possible to reconstruct.
How to fix it
Fill the number in from your invoicing system. Factlint reports it as `needs_input` and never fabricates a default value.
XML correction example
<!-- rsm:ExchangedDocument/ram:ID absent -->
<ram:ID>FA-2026-0042</ram:ID>