Indicated the version of UBL the message is based on

Cardinality
1..1
Namespace
cbc urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2
Fixed value
2.1
Rules
Identifier/Error message Flag
NONAT-T14-R016
UBL version must be 2.1
fatal
EHF-T14-B00201
Element 'cbc:UBLVersionID' MUST contain value '2.1'.
warning