BR-30
EN 16931
FATAL
Official rule text
If both Invoice line period start date (BT-134) and Invoice line period end date (BT-135) are given then the Invoice line period end date (BT-135) shall be later or equal to the Invoice line period start date (BT-134).
What this error means
This is a mandatory field rule: the business term referenced above must be present in every invoice, and it is missing (or empty) in yours.
How to fix it
- Add the element for the business term (BT) named in the rule text.
- An empty element does not count - the field must carry a value.
- Check you placed it at the correct level (document, party, or line).
Related rules
Fix it faster
Paste your invoice XML in our free validator - every finding comes with its rule ID. Then generate, convert and render compliant invoices through one API.