@Akash Chopra Have you enabled ADLS Gen 2 in your Storage account, If so (not currently supported as a destination for diagnostic settings even though they may be listed as a valid option in the Azure portal.)
You should not use an existing storage account that has other, non-monitoring data stored in it so that you can better control access to the data. If you are archiving the Activity log and resource logs together though, you may choose to use the same storage account to keep all monitoring data in a central location.
The storage account needs to be in the same region as the resource being monitored if the resource is regional.
Note: If diagnostic data isn't being collected or you're having trouble viewing it in the portal, reinstalling the agent might help. This removes the agent, but keeps all existing diagnostic data in your storage account. After the agent is removed, you can re-enable diagnostics for this virtual machine.
This article will help you in Diagnostics data is not logged to Azure Storage(Determine if none of the data is appearing or some of the data is appearing.)
Additional information: Log data is stored in either Blob or Table storage. For more information on Store and view diagnostic data in Azure Storage see here.
Hope this helps!
Kindly let us know if the above helps or you need further assistance on this issue.
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