Message type: E = Error
Message class:  CNVA_20400_CHECK - Messages for contorlling areas checks 
Message number: 037
Message text: No cycle merges found (for example assessment cycles, distributions)
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The SAP error message CNVA_20400_CHECK037 indicates that the system could not find any cycle merges during the execution of an assessment or distribution cycle. This typically occurs in the context of controlling (CO) processes, particularly when dealing with cost allocations.
Cause: No Valid Cycle Defined: The error may arise if there are no valid assessment or distribution cycles defined in the system for the specified period. Cycle Not Active: The cycle might not be active or may not have been properly configured. Incorrect Parameters: The parameters or selection criteria used to execute the cycle may not match any existing cycles. Missing Master Data: Required master data (like cost centers, internal orders, etc.) may be missing or incorrectly set up. Period Locking: The period for which the cycle is being executed may be locked or closed.
Solution: Check Cycle Configuration: Go to the configuration of the assessment or distribution cycle in the SAP system (Transaction code: OKAB for assessment cycles
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