DT-CIUS-PT-032.1
The BT-34 does not meet the defined format: alphanumeric with size between 1 and 50.
error: the document is invalid
What the rule checks
As the rule set's publisher wrote it. The rule runs on every element the context matches, and fails where the test is false; the validator reports the line of that element.
Context
//ubl:Invoice/cac:AccountingSupplierParty/cac:Party/cbc:EndpointID | //cn:CreditNote/cac:AccountingSupplierParty/cac:Party/cbc:EndpointID
Test
matches(.,'^(.{1,50})$')
Checked with Portugal CIUS-PT Invoice (UBL), Portugal CIUS-PT Credit Note (UBL)