BR-KSA-34
The invoice counter value (KSA-16) contains only digits.
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 | /cn:CreditNote
Test
matches(cac:AdditionalDocumentReference/cbc:UUID, '^[0-9]*$')
Checked with Saudi Arabia ZATCA Tax Invoice (UBL), Saudi Arabia ZATCA Simplified Tax Invoice (UBL)