Message type: E = Error
Message class:  FKKINV_ID_XX_ODN - ODN Message in Convergent Invoicing 
Message number: 012
Message text: Country of document &1 must be unique
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The SAP error message FKKINV_ID_XX_ODN012 indicates that there is an issue with the uniqueness of the document country in the context of the billing or invoicing process. This error typically arises in the SAP Convergent Charging or SAP Contract Accounts Receivable and Payable (FI-CA) modules, where the system requires that the country of the document must be unique for certain operations.
Cause: The error is triggered when the system detects that there are multiple entries with the same document country in a context where uniqueness is required. This can happen due to: Duplicate Entries: There may be duplicate billing documents or invoices that have the same country code.
Configuration Issues: The system configuration may not be set up correctly to handle multiple entries for the same country. Data Migration Issues: If data has been migrated from another system, it may have resulted in duplicate entries. Incorrect Document Type: The document type being used may not be
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