[UBL-SR-23]-Seller tax representative VAT identifier shall occur maximum once, if the Seller has a tax representative
UBL-SR-23pxs-taxdata:TaxData/pxs-taxdata:ReportedTransaction/pxs-taxdata:ReportedDocument/cac:TaxRepresentativeParty(count(cac:Party/cac:PartyTaxScheme/cbc:CompanyID) <= 1)