cvc-datatype-valid.1.2.1:Invoice field value does not match the required data format
A value in your invoice does not match the data format required by the XML Schema. This typically means a number, date, or other value is formatted incorrectly — for example, using a comma instead of a dot for decimals (1.234,56 instead of 1234.56), or a date in DD/MM/YYYY format instead of the required YYYY-MM-DD (ISO 8601).
Engine Classification
Parse the error message to identify the invalid value and target type, then normalize common formatting issues (decimal separator, date format, boolean)
Confidence: 75% · Applied automatically in pipeline
What is cvc-datatype-valid.1.2.1?
cvc-datatype-valid.1.2.1 is a fatal validation rule defined in the xsd specification. It validates the __from_error_message__ element in the UBL invoice XML.
When this rule fires, the invoice is non-compliant and will be rejected by Peppol access points and national validation services. The sending system receives a rejection response and the invoice does not reach the buyer.
Target path: __from_error_message__
Why This Error Matters
cvc-datatype-valid.1.2.1 is a hard failure. Invoices that trigger this rule are rejected at the access point and never reach the recipient. In Peppol networks, this means your sending system receives an MLR (Message Level Response) with a rejection status. The invoice must be corrected and re-sent, adding delay to your payment cycle.
Invoice Navigator can automatically correct this error in your pipeline. The fix is applied with full audit evidence, so your compliance trail remains intact.
Validator Behavior
- ·Causes invoice rejection
- ·Error returned: cvc-datatype-valid.1.2.1
- ·Specification: xsd
How to Fix It
Check the error details
The error message identifies the invalid value and what type was expected. For example: '1.234,56 is not a valid value for decimal' means the number uses continental formatting.
Fix number formatting
Use dot (.) as decimal separator, no thousand separators: 1234.56, not 1.234,56 or 1,234.56.
Fix date formatting
Use ISO 8601 format: YYYY-MM-DD (e.g., 2026-03-12), not DD/MM/YYYY or MM/DD/YYYY.
Update software locale settings
If this error occurs consistently, check your invoicing software's locale and number format settings for XML export.
XML Example
Generic example based on the rule's target XPath. Your actual XML structure may differ.
<!-- Triggers validation error --> <__from_error_message__></__from_error_message__>
<!-- Corrected --> <__from_error_message__>VALID_VALUE</__from_error_message__>
Technical Reference
__from_error_message__Common Causes
- ·UK or continental number formatting with comma decimals (1.234,56)
- ·Dates in DD/MM/YYYY instead of ISO 8601 YYYY-MM-DD
- ·Thousand separators in numeric fields (1,234.56)
- ·Boolean values as Yes/No instead of true/false
- ·Currency amounts with locale-specific formatting
Seeing this in production? The API handles cvc-datatype-valid.1.2.1 automatically. See the fix response →
Commonly Seen In
Related Errors
Last updated: 12 March 2026
Handle cvc-datatype-valid.1.2.1 Automatically in Your Pipeline
The compliance engine auto-remediates this error with controlled safety policies and evidence pack generation.