Hello Thangavel Vaiyapuri,
Thank you for posting your query here!
When you expand a basic disk in Azure, it may convert to a dynamic disk if the disk is part of a storage pool. This is because Storage Spaces, can group two or more drives together in a storage pool and then use capacity from that pool to create virtual drives called storage spaces.
Please note that if you are running Storage Spaces Direct in a virtualized storage environment, including in Azure, resizing or changing the characteristics of the storage devices used by the virtual machines isn't supported and will cause data to become inaccessible.
To use Storage Spaces, you can add more Disks - but can't resize an existing one, to increase the pool. Similar post for reference: https://learn.microsoft.com/en-us/answers/questions/1315027/convert-to-dynamic-disk-when-i-extend-disk-on-vm
I hope this helps! Please let me know if the issue persists or if you have any other questions.
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