Message type: E = Error
Message class:  CNV_PE_BOD - Messages in context of OBT/ES interaction 
Message number: 018
Message text: ES data model exists already
In embedded specification (ES), the data model is identified by the root
template ID of the posting engine table parameter. Therefore, it is not
possible to generate an ES data model for the area, which is copied from
the template of another existing area.
An error <LB>DMOD_ALREADY_EXISTS </>is raised.
The workaround solution is to choose another selection method for the
current area, so that <ZH>no </>ES data model will be generated.
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_PE_BOD018 indicates that there is an issue related to the existence of a data model in the context of a data migration or conversion process. This error typically arises during the execution of a data migration project, particularly when using SAP's Conversion Tools or Data Migration tools.
Cause: The error message CNV_PE_BOD018 occurs when the system detects that a data model you are trying to create or modify already exists in the database. This can happen due to: Duplicate Data Models: The data model you are trying to create has already been defined in the system. Incomplete Cleanup: Previous migration attempts may not have been fully cleaned up, leaving remnants of old data models.
Configuration Issues: There may be configuration settings that are causing the system to misinterpret the existence of the data model.
Solution: To resolve the error, you can take the following steps: Check Existing Data Models: Use transaction codes like SE11 (Data
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