Hi @MS Techie ,
Service Health alerts are one type of activity log alerts and Activity logs alerts are always SEV 4 by design. We cannot change the severity of activity log alerts.
If you need to define a different severity, then you need to create log search alerts.
You can forward the activity logs to log analytics workspace by enabling diagnostic settings.
Then you can query "AzureActivity" table with category service Health and create a log search alert and can keep a severity they need.
AzureActivity| where CategoryValue == "ServiceHealth"
Please note that these alerts will be chargeable then as Log search alerts have cost associated with them, but Activity log alerts are free of any cost.
Also if you like, you can provide feedback to our product team regarding your requirement:
Here is the link for the same:
Azure Monitor: https://feedback.azure.com/forums/913690-azure-monitor
Our product team reviews this regularly and based on number of votes and feasibility, they try to incorporate the suggestion in next release. Your feedback and ideas are valuable to us to make our product better. Please feel free to submit the suggestions in this forum.