URI identifier required for email communication

Error FX-SCH-A-000869 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

URIID is missing from EmailURIUniversalCommunication or does not occur exactly once. URIID must be present exactly once.

What the rule means

URIID provides the URI value for the contact’s email communication. The rule requires exactly one such entry.

Please add the URI identifier for the invoicee’s email communication

URIID is missing or appears more than once in the invoicee’s email communication. You can correct this by including exactly one URIID.

What to do
  1. Find EmailURIUniversalCommunication for the invoicee’s contact.
  2. Include exactly one URIID element inside it.
  3. Generate the invoice again and validate it once more.
What it looks like
✗ Triggers the message 
<ram:EmailURIUniversalCommunication/>
✓ Correct 
<ram:EmailURIUniversalCommunication>
  <ram:URIID/>
</ram:EmailURIUniversalCommunication>
Technical details

Within EmailURIUniversalCommunication, the number of direct URIID elements must be exactly one.

Where the rule applies

The rule applies to the contact’s email communication in InvoiceeTradeParty.

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