# F-CRN006

Source: https://xmlvalid.com/rules/F-CRN006

> Invalid CreditNote/ID (Creditnote number). Must contain a value.

- Level: error
- Rule sets: OIOUBL 2.1 Credit Note rules (Denmark) 1.17.2
- Context: `doc:CreditNote`
- Test: `normalize-space(cbc:ID) != ''`

Validate a document against these rules: https://xmlvalid.com/validate