Message type: E = Error
Message class:  CNV_NCE_BAS - Number conversion engine: messages 
Message number: 159
Message text: NR interval &1: interval cannot be excluded (one-to-one mappings exist)
You have chosen the rule 'No Conversion' for the corresponding number
range interval, although one-to-one mapping values exist for the numbers
that belong to it.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Choose the 'One-to-one' rule for the number range interval.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message CNV_NCE_BAS159 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 issue with the mapping of intervals in the data being processed. Specifically, it suggests that there are one-to-one mappings that prevent the exclusion of a certain interval.
Cause: The error message "interval cannot be excluded (one-to-one mappings exist)" indicates that: There are existing one-to-one mappings for the specified interval, which means that each entry in the source data corresponds directly to an entry in the target data. The system is trying to exclude an interval that is still being referenced by these mappings, which is not allowed.
Solution: To resolve this error, you can take the following steps: Review Mappings: Check the mappings defined in your migration or conversion project. Ensure that there are no one-to-one mappings that reference the interval you are trying to exclude. Adjust
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