Message type: E = Error
Message class:  CNV_21538 - Date Type Rename 
Message number: 001
Message text: Mapping not maintained for renaming date type
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The SAP error message CNV_21538001: Mapping not maintained for renaming date type typically occurs during data migration or conversion processes, particularly when using the SAP Landscape Transformation (SLT) or SAP Data Services tools. This error indicates that there is a missing mapping for a date type field that is being renamed or transformed during the data migration process.
Cause: Missing Mapping: The primary cause of this error is that the mapping for a specific date type field has not been defined in the transformation rules. This can happen if the field is not included in the mapping configuration or if the mapping is incomplete. Data Type Mismatch: There may be a mismatch between the source and target data types, especially if the date format or representation is different.
Configuration Issues: Incorrect or incomplete configuration in the data migration tool can lead to this error.
Solution: Check Mapping Configuration: Go to the mapping configuration in your data migration
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