Message type: E = Error
Message class:  CNV_21537 - Reason for Action Rename 
Message number: 011
Message text: A blank field may be filled with personnel action reason &1
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The SAP error message CNV_21537011 indicates that a blank field in a personnel action is being filled with a personnel action reason that is not appropriate or valid for the context. This error typically arises during data migration or when processing personnel actions in the SAP system.
Cause: Data Migration Issues: This error often occurs during data migration processes, especially when using tools like SAP's Legacy System Migration Workbench (LSMW) or other data upload methods. If the source data contains blank fields that are expected to be filled with valid personnel action reasons, this error will be triggered.
Configuration Issues: The personnel action reasons may not be properly configured in the system, or there may be inconsistencies in the data that do not align with the expected values in the target system. Business Logic Violations: The business rules defined in the SAP system may not allow certain personnel action reasons to be used in
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