Message type: E = Error
Message class:  FKK_ID_AR - ARGENTINA: Legal report message class 
Message number: 018
Message text: Input datasets have different reporting periods
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The SAP error message FKK_ID_AR018, which states "Input datasets have different reporting periods," typically occurs in the context of financial transactions or reporting within the SAP system, particularly in the area of contract accounts receivable and payable (FI-CA). This error indicates that the datasets you are trying to process or analyze have mismatched reporting periods, which prevents the system from executing the desired operation.
Cause: Mismatched Reporting Periods: The most common cause of this error is that the datasets being processed (e.g., invoices, payments, or other financial documents) belong to different fiscal periods. For example, one dataset may be from January while another is from February. Incorrect Selection Criteria: The selection criteria used to retrieve the datasets may inadvertently include records from different periods. Data Entry Errors: Manual data entry errors can lead to records being assigned to incorrect periods.
Solution: Check Reporting Periods: Review the datasets involved in the transaction or report. Ensure that all
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