Message type: E = Error
Message class:  FKK_ID_IT - Messages for FI-CA: VAT reporting for Italy 
Message number: 131
Message text: &1 has 2 different business partners; they must be identical
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The SAP error message FKK_ID_IT131 indicates that there is a discrepancy in the business partner data associated with a particular transaction or document. Specifically, it means that the system has identified two different business partners where it expects them to be identical. This can occur in various scenarios, such as when processing invoices, payments, or other financial transactions in the SAP Convergent Charging or Contract Accounts Receivable and Payable (FI-CA) modules.
Cause: Data Entry Errors: The most common cause is that the same entity has been entered into the system with different identifiers (e.g., different business partner numbers).
Configuration Issues: There may be configuration settings that are not aligned, leading to the system treating the same entity as two different business partners. Master Data Issues: There could be inconsistencies in the master data for business partners, such as different addresses or contact information that cause the system to recognize them as separate entities. Transaction Errors:
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