Message type: E = Error
Message class:  CNV_20320_CHECK - Messages for check functions (Activity Types merge) 
Message number: 003
Message text: Implicit activity type merge found
An <DS:TX.CNV_MBT_IMPLICIT_MERGE>implicit merge</> into a activity type
was detected. This happens for example when activity types will be
merged, but the mapping only contains a part of the source activity
types.
To avoid unwanted merges, you must specify mapping values for all the
source values of the target activity types. The key of the target is
stored in the context of this message.
You cannot run the transformation solution Controlling Area Merge
because certain prerequisites have not been met. Please change your
mapping accordingly.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message CNV_20320_CHECK003 indicates that there is an implicit activity type merge found during a conversion or migration process, typically related to the SAP S/4HANA migration or data conversion projects. This error usually arises when there are inconsistencies in the activity types being used in the system, particularly when the same activity type is being referenced in multiple contexts or when there are overlaps in the definitions of activity types.
Cause: Duplicate Activity Types: The error may occur if there are multiple activity types defined in the system that are implicitly merged, leading to confusion in the data conversion process. Inconsistent Data: If the data being migrated contains references to activity types that are not clearly defined or are duplicated, this can trigger the error.
Configuration Issues: Misconfigurations in the system settings related to activity types can also lead to this error.
Solution: Review Activity Types: Check the definitions of the activity types in
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