@Ravi Nalla Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
- Can you retry the operation again(How are trying to migrate (Portal, PS or Cli)
- Step-by-Step: Migrate your classic Cloud Services to ARM–Storage Migration.
- Recommended to use the below link and delete if there is any orphan disk object and images that might be impacting the storage account migration.
https://learn.microsoft.com/en-us/azure/virtual-machines/migration-classic-resource-manager-ps?toc=%2Fazure%2Fvirtual-machines%2Fwindows%2Ftoc.json#step-52-migrate-a-storage-account
Errors that commonly occur during Classic to Azure Resource Manager migration
If the issue still persists. I wish to engage with you offline for a closer look and provide a quick and specialized assistance,
Hope this helps!
Kindly let us know if the above helps or you need further assistance on this issue.
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