Email communication URI identifier required

Error FX-SCH-A-000932 Factur-X

Element 'ram:URIID' 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

ram:URIID is missing from ram:EmailURIUniversalCommunication or occurs more than once. It must occur exactly once.

What the rule means

ram:URIID contains the identifier for the payer contact's email communication.

Please provide the email communication URI identifier

ram:URIID is missing from the payer contact's email communication or appears more than once. Providing exactly one element resolves the structure issue.

What to do
  1. Add ram:URIID to ram:EmailURIUniversalCommunication if it is missing.
  2. Remove any extra ram:URIID elements so that exactly one remains.
  3. Generate the invoice again and validate it.
What it looks like
✗ Triggers the message 
<ram:EmailURIUniversalCommunication/>
✓ Correct 
<ram:EmailURIUniversalCommunication>
  <ram:URIID>mailto:contact@example.com</ram:URIID>
</ram:EmailURIUniversalCommunication>
Technical details

The rule counts the direct ram:URIID elements within ram:EmailURIUniversalCommunication and requires exactly one.

Where the rule applies

ram:URIID is checked in ram:EmailURIUniversalCommunication for the payer's contact.

Context (rule/@context)
/rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeSettlement/ ram:PayerTradeParty/ram:DefinedTradeContact/ram:EmailURIUniversalCommunication
Test expression (assert/@test)
count(ram:URIID)=1