Message type: E = Error
Message class:  CNV_NCE_BAS - Number conversion engine: messages 
Message number: 453
Message text: Conflict with another unique target number range interval detected
There is a conflict using shifting rule for the object, because a
different rule was selected for the same target number range interval in
a different row.
If you confirm the rule here, the rules for any other row having the
same target interval will also be changed accordingly.
If you do not confirm the rule here, the rule will be initialized.
Pease check your decision.
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_NCE_BAS453 indicates that there is a conflict with another unique target number range interval during a data migration or conversion process. This typically occurs in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other data conversion scenarios.
Cause: The error arises when the system detects that the target number range you are trying to use for a specific object (like a document, customer, vendor, etc.) overlaps with an existing number range that is already defined in the system. This can happen if: You are trying to assign a number range that is already in use by another object. There are conflicting settings in the configuration of number ranges. The number range intervals are not properly defined or have been incorrectly set up.
Solution: To resolve this error, you can follow these steps: Check Existing Number Ranges: Go to the transaction code SNRO (Number Range Objects) and check the
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