@AnuragSingh-MSFT - Thanks for reaching out to us.
Please try to modify the alert rule configuration to trigger only on the 'Succeeded' status. This adjustment will ensure that the runbook is triggered only once for the same event, preventing concurrent execution, and ensuring sequential processing as required.
For more information on configuring Azure Automation Runbook and activity log alerts, please refer to doc here: https://docs.microsoft.com/en-us/azure/automation/.
Hope this helps. and please feel free to reach out if you have any further questions.
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