# CII-SR-466 Buyer contact: person name or department name, not both

In CII, the buyer contact point (BT-56) is either ram:PersonName or ram:DepartmentName in ram:BuyerTradeParty/ram:DefinedTradeContact. CII-SR-466 ("Only one BT-56 element is allowed on an invoice") fails when both elements are present. The CEN validation artefacts flag the rule as a warning; the KoSIT configuration for XRechnung 3.0.2 of 2026-08-31 raises it to an error for XRechnung in CII syntax. The buyer contact itself stays optional.

## Problem Description

> **ERROR**: EN 16931 syntax rule for CII (CEN, CII-SR)

> **Where CII-SR-466 is checked**
>
> A validator checks an e-invoice in stages. First the file must be well-formed XML that matches the UBL or CII schema (XSD). Then the EN 16931 business rules run: BR core rules, BR-CO calculations, BR-CL code lists, BR-DEC decimals and VAT-category rules such as BR-S. Next come the national or network rules that BT-24 selects: BR-DE for XRechnung, PEPPOL-EN16931 for Peppol BIS Billing. The report lists every failed rule: one error means reject, warnings alone still mean accept. CII-SR-466: EN 16931 syntax rule for UBL or CII, reported in the stage “EN 16931 rules”.

## Context and Significance

Buyers often name both a contact person and a department in the order, and both are copied into the CII contact. Since the KoSIT release of 2026-08-31 that combination fails XRechnung validation.

## Solution

Keep one value for BT-56: ram:PersonName for a named person, or ram:DepartmentName for a department, and remove the other element. If the buyer gave no contact, you can omit the whole ram:DefinedTradeContact block.

- [Validate XML](/en/xrechnung-validator?source=resource&rule=CII-SR-466)
- [Convert invoice](/en/pdf-to-xrechnung?source=resource&rule=CII-SR-466)

## Valid Examples

- ram:PersonName = "Jonas Weber"
- ram:DepartmentName = "Purchasing" (no PersonName)

## Invalid Examples

- ram:PersonName = "Jonas Weber" and ram:DepartmentName = "Purchasing"

## Code Examples

### Valid XML
```
<ram:DefinedTradeContact>
  <ram:DepartmentName>Purchasing</ram:DepartmentName>
</ram:DefinedTradeContact>
```

### Invalid XML
```
<ram:DefinedTradeContact>
  <ram:PersonName>Jonas Weber</ram:PersonName>
  <ram:DepartmentName>Purchasing</ram:DepartmentName>
</ram:DefinedTradeContact>
```

## Affected Fields

- [BT-56 Buyer contact point](/resources/xrechnung/bt-56-buyer-contact-point)

## Related Rules

- [CII-SR-465](/resources/kosit-validator-errors/cii-sr-465-seller-contact-person-or-department-name)

## Validation Tools

- [Official KoSIT Validator](https://github.com/itplr-kosit/validator): Run the official KoSIT validator with the XRechnung configuration to check EN 16931 and XRechnung rules.
- [Convert PDF to XRechnung](/pdf-to-xrechnung): Find validation errors during conversion and review each correction.

## Related Resources

- [Official Specification](https://github.com/ConnectingEurope/eInvoicing-EN16931)
- [Test Suite](https://github.com/itplr-kosit/xrechnung-testsuite)
- [All validation errors](/resources/kosit-validator-errors): Overview of the EN 16931, XRechnung and Peppol validation rules explained here.