Hi @Nepali Sandhya ,
Normally, to export and view the audit logs, we can refer to the instructions below to export the results to csv files via either the Compliance portal or PowerShell, then formatting the results using the Power Query editor in Excel.
Export, configure, and view audit log records
Per my test, there are no weird "column" part in excel when using these steps.
So, you can try using the recommended steps in the linked article above to export the audit logs again and check the result. Otherwise, you can manually edit the current excel file to remove the "column" part.
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