ram:CompleteNumber required in fax communication

Error FX-SCH-A-000819 Factur-X

Element 'ram:CompleteNumber' must occur exactly 1 times.

Mandatory rule: As long as it is violated, the invoice is invalid and will be rejected by validators.
What is wrong

The ram:CompleteNumber element is missing from ram:FaxUniversalCommunication. This element must occur there exactly once.

What the rule means

ram:CompleteNumber contains the contact’s complete fax number. The rule requires exactly one such element.

Please add the delivery recipient’s fax number

The contact’s fax communication is missing ram:CompleteNumber. Add this element exactly once.

What to do
  1. Locate ram:DefinedTradeContact under ram:ShipToTradeParty.
  2. Add exactly one ram:CompleteNumber element inside ram:FaxUniversalCommunication.
  3. Regenerate the invoice and validate it again.
What it looks like
✗ Triggers the message 
<ram:FaxUniversalCommunication/>
✓ Correct 
<ram:FaxUniversalCommunication>
  <ram:CompleteNumber>+33123456789</ram:CompleteNumber>
</ram:FaxUniversalCommunication>
Technical details

The check counts the direct child elements ram:CompleteNumber of ram:FaxUniversalCommunication and requires exactly one.

Where the rule applies

The rule applies to ram:FaxUniversalCommunication within the ram:DefinedTradeContact of the delivery recipient ram:ShipToTradeParty.

Context (rule/@context)
/rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeDelivery/ ram:ShipToTradeParty/ram:DefinedTradeContact/ram:FaxUniversalCommunication
Test expression (assert/@test)
count(ram:CompleteNumber)=1