Message

Element 'cbc:ID' MUST contain value 'VAT'.

Context
/ubl:OrderCancellation/cac:BuyerCustomerParty/cac:Party/cac:PartyTaxScheme/cac:TaxScheme/cbc:ID
Test
normalize-space(text()) = 'VAT'
Usage
/ ubl:OrderCancellation / cac:BuyerCustomerParty / cac:Party / cac:PartyTaxScheme / cac:TaxScheme / cbc:ID