# F-INV124

Source: https://xmlvalid.com/rules/F-INV124

> PrepaidAmount is mandatory when PrepaidPayment/PaidAmount elements are present

- Level: error
- Rule sets: OIOUBL 2.1 Invoice rules (Denmark) 1.17.2
- Context: `doc:Invoice/cac:LegalMonetaryTotal`
- Test: `count(../cac:PrepaidPayment/cbc:PaidAmount) and not(cbc:PrepaidAmount)`

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