# CII-SR-450

Source: https://xmlvalid.com/rules/CII-SR-450

> Only one buyer identifier should be present (either the ID or the Global ID)

- Level: warning
- Rule sets: EN 16931 rules (CII) 1.3.17, EN 16931 rules 1.3.16 (CII), EXTENDED-CTC-FR rules (CII) 1.4.0.04
- Context: `/rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeAgreement`
- Test: `(not(ram:BuyerTradeParty/ram:ID) and ram:BuyerTradeParty/ram:GlobalID) or (ram:BuyerTradeParty/ram:ID and not(ram:BuyerTradeParty/ram:GlobalID)) or (not(ram:BuyerTradeParty/ram:ID) and not(ram:BuyerTradeParty/ram:GlobalID))`

## Why it fails

- The buyer has both `ram:BuyerTradeParty/ram:ID` and `ram:GlobalID`, for example your own customer number and a GLN.

## How to fix it

- EN 16931 has a single buyer identifier (BT-46). Keep one of the two: the `ram:GlobalID` with its `schemeID` when the buyer has a registered identifier such as a GLN, otherwise `ram:ID`. Your own customer number can go in the buyer reference (BT-10) instead.

Validate a document against these rules: https://xmlvalid.com/validate