How do I fix DE-R-022?

Duplicate attachment filename. All attached documents in German invoices must have unique filenames (case-insensitive) in element BT-125. You can also use Invoice Navigator's compliance engine to correct this automatically in your pipeline.

Is DE-R-022 a critical error?

Yes, DE-R-022 is a critical error that will cause invoice rejection. It must be fixed before submission.

Can DE-R-022 be automatically fixed?

Many instances of DE-R-022 can be automatically corrected using Invoice Navigator's compliance engine. The fix is applied in your pipeline with full audit evidence.

errorDEUPEPPOL_BIS

`DE-R-022`:Duplicate attachment filename. All attached documents in German invoices must have unique filenames (case-insensitive) i

Duplicate attachment filename. All attached documents in German invoices must have unique filenames (case-insensitive) in element BT-125.

Severity

Fatal

Rule set

PEPPOL_BIS

Country

DEU

Fix type

CONFIRM

Confidence

80%

Engine Classification

Requires user confirmation before application

What is DE-R-022?

DE-R-022 is a fatal validation rule defined in the PEPPOL_BIS specification (DEU national rules). It validates the CityName element under DeliveryLocation > Address 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: //cac:Delivery/cac:DeliveryLocation/cac:Address/cbc:CityName

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Why This Error Matters

Invoice will be rejected by German XRechnung validators. German e-invoicing has specific format requirements for payment details, contact information, and attachments.

DE-R-022 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.

Validator Behavior

·Causes invoice rejection
·Rejected by PEPPOL Access Points
·Rejected by XRechnung endpoints
·Error returned: DE-R-022
·Specification: PEPPOL_BIS

XML Example

Generic example based on the rule's target XPath. Your actual XML structure may differ.

Before

<!-- Missing or empty element triggers cbc:CityName error -->
<cbc:CityName></cbc:CityName>

After

<!-- Provide the required value -->
<cbc:CityName>VALID_VALUE</cbc:CityName>

Technical Reference

XPath//cac:Delivery/cac:DeliveryLocation/cac:Address/cbc:CityName

SpecPEPPOL_BIS

Operationset_default

StrategyEnsure delivery city name is present when delivery section exists

Common Causes

·Attached document filenames not unique
·BT-125 contains duplicate filename (case insensitive)
·Multiple attachments with same name in BG-24
·cbc:EmbeddedDocumentBinaryObject/@filename duplicated
·File naming collision in additional supporting documents

Seeing this in production? The API handles DE-R-022 automatically. See the fix response →

Last updated: 27 February 2026

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Handle DE-R-022 Automatically in Your Pipeline

The compliance engine auto-remediates this error with controlled safety policies and evidence pack generation.

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DE-R-022:Duplicate attachment filename. All attached documents in German invoices must have unique filenames (case-insensitive) i