Message type: E = Error
Message class:  CNV_NCE_BAS - Number conversion engine: messages 
Message number: 018
Message text: Number interval &1 (subobject &2) does not exist in NRIV
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The SAP error message CNV_NCE_BAS018 indicates that there is an issue with number ranges in the system. Specifically, the message states that a number interval (or number range) for a specific subobject does not exist in the NRIV (Number Range Interval) table. This can occur during data migration or when trying to create or assign a number range to an object that has not been properly defined.
Cause: Missing Number Range Definition: The number range for the specified subobject has not been defined in the system. Incorrect Configuration: The configuration for the number range might be incorrect or incomplete. Data Migration Issues: If this error occurs during a data migration process, it may indicate that the migration tool is trying to use a number range that has not been set up in the target system. Authorization Issues: Sometimes, the user may not have the necessary authorizations to access or create the number range.
Solution: Check Number Range
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