Hi @Anil Kumar
Azure does not natively store or display the exact timestamp for when a disk was detached. However, you can use Azure Activity Logs to trace back to when a disk was detached. The Activity Log contains events related to all the operations on your resources, including when disks are detached from virtual machines.
On Azure Portal Navigate to the subscription:
In the Activity Log, set the Scope
to the specific resource group or subscription that contains the disk.
You also can try Azure Orphan Resource
https://techcommunity.microsoft.com/t5/fasttrack-for-azure/azure-orphan-resources/ba-p/3492198
Get in touch if you need more help with this issue.
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