Message type: E = Error
Message class:  /ACCGO/CAS_FLLW_MSG -  
Message number: 651
Message text: Implicit optionality evaluated
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message /ACCGO/CAS_FLLW_MSG651 Implicit optionality evaluated typically relates to the SAP S/4HANA system, particularly in the context of the Advanced Compliance Reporting (ACR) or similar modules where optionality in data fields is evaluated during processing.
Cause: This error message indicates that there is an issue with the evaluation of optional fields in a data structure or report. It often arises when the system encounters a situation where it expects certain fields to be filled based on the configuration or the data being processed, but those fields are either missing or not correctly defined as optional.
Solution: To resolve this error, you can take the following steps: Check Configuration: Review the configuration settings related to the reporting or data processing module you are working with. Ensure that the optional fields are correctly defined and that the system is set up to handle them appropriately. Data Validation: Validate the data being processed. Ensure that all required
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