Message type: E = Error
Message class:  UA_SM1 - Structure Maintenance 
Message number: 063
Message text: The sequence number must be unique
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The SAP error message UA_SM1063, which states "The sequence number must be unique," typically occurs in scenarios where a sequence number is expected to be unique within a certain context, such as in document processing, transaction entries, or data records. This error can arise in various modules, including Sales and Distribution (SD), Materials Management (MM), or others where sequence numbers are utilized.
Cause: Duplicate Sequence Numbers: The most common cause of this error is that the system has detected a duplicate sequence number in the data being processed. This can happen if: The same sequence number is being used for multiple entries. There is a data entry error where the same number is mistakenly entered more than once. Data was imported or uploaded into the system with non-unique sequence numbers.
Configuration Issues: In some cases, the configuration settings for number ranges or sequence numbers may not be set up correctly, leading to conflicts. Concurrency Issues: If multiple
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