Message

Value MUST be part of code list 'Recommendation 21 (UN/ECE)'.

Context
/ubl:DespatchAdvice/cac:Shipment/cac:TransportHandlingUnit/cbc:TransportHandlingUnitTypeCode
Test
(some $code in $clUNECERec21 satisfies $code = normalize-space(text()))
Code lists
Recommendation 21 (UN/ECE)
Usage
/ ubl:DespatchAdvice / cac:Shipment / cac:TransportHandlingUnit / cbc:TransportHandlingUnitTypeCode