# BR-63

Source: https://xmlvalid.com/rules/BR-63

> The Buyer electronic address (BT-49) shall have a Scheme identifier.

- Level: error
- Rule sets: EN 16931 rules (UBL) 1.3.17, EN 16931 rules 1.3.16 (UBL), EXTENDED-CTC-FR rules (UBL) 1.4.0.04, Romanian RO e-Factura rules (UBL) 1.0.9
- Context: `cac:AccountingCustomerParty/cac:Party/cbc:EndpointID`
- Test: `exists(@schemeID)`

> The Buyer electronic address (BT-49) shall have a Scheme identifier.

- Level: error
- 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, Factur-X BASIC WL rules 1.09, Factur-X EN 16931 rules 1.09.2, Factur-X EXTENDED rules 1.09.2
- Context: `/rsm:CrossIndustryInvoice`
- Test: `normalize-space(rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeAgreement/ram:BuyerTradeParty/ram:URIUniversalCommunication[1]/ram:URIID/@schemeID) != '' or not (rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeAgreement/ram:BuyerTradeParty/ram:URIUniversalCommunication)`

## Why it fails

- The buyer's `cbc:EndpointID` (`ram:URIUniversalCommunication/ram:URIID` in CII) has no `schemeID`.

## How to fix it

- Add the EAS code of the buyer's address as `schemeID`; for a German public buyer's Leitweg-ID it is `0204`.

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