Message type: E = Error
Message class:  CNV_20200_CHECK - Messages for check functions (company code merge) 
Message number: 258
Message text: Valuation is on level "several plants"
Valuation is on level "several plants" (TCURM-BWKRS_CUS=2)
Warning with action required
These are very extraordinary customizing settings.
The transformation solution Company Code Merge should be possible.
However,  we recommend that you contact SAP for support by creating a
ticket using component CA-LT-CNV.
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_20200_CHECK258 with the description "Valuation is on level 'several plants'" typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that there is an inconsistency in the valuation level settings for materials in the system.
Cause: Valuation Level Settings: The error arises when the valuation level for materials is set to "Plant" in some instances and "Company Code" in others. This inconsistency can occur if the materials are defined with different valuation levels across different plants or if the migration data does not align with the expected valuation level. Data Migration Issues: During data migration, if the source system has materials with different valuation levels and the target system expects a uniform valuation level, this error can be triggered.
Solution: Check Valuation Level Settings: Go to the material master data in the SAP system and check the valuation level settings
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