Message type: E = Error
Message class:  CNV_20320_CHECK - Messages for check functions (Activity Types merge) 
Message number: 021
Message text: Activity Type Check not needed for date dependent mergers
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The SAP error message CNV_20320_CHECK021 indicates that there is an issue related to the activity type check during a date-dependent merger in the context of a data migration or conversion process. This error typically arises in the context of SAP's Conversion and Migration tools, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: The error message suggests that the system is attempting to perform an activity type check that is not necessary for date-dependent mergers. This can occur due to:
Configuration Issues: The configuration settings for the activity types or the merger process may not be set up correctly. Data Inconsistencies: There may be inconsistencies in the data being processed, such as incorrect or missing activity type assignments. Process Logic: The logic defined in the migration or conversion process may not align with the expected behavior for date-dependent mergers.
Solution: To resolve the error, you can take the following steps: Review Configuration: Check the configuration
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