Hi Lawrence Wong,
Thank you for patience while reviewing the issue
Based upon your query there will be the several issue might be cause you can try the following step to resolve you issue
First, please confirm whether the network, disk and VM are in the same resource group. If the network, disk and VM are in different resource groups, this could cause issues, even if the validation is successful. To resolve this, gather all the resources you want to move into a single resource group in Subscription A, and then try moving the resources to Subscription B again.
And you provided another comment with more information about the issue. The problem arises because a resource with the same name already exists, which is why the issue occurs. Please rename the conflicting resource and try again.
The error message states: "which have the same name as a resource in the target resource group."
Please refer this document Scenario for move across subscriptions
Note: Before moving the VM and its associated resources, make sure to back up your data and create snapshots of the disks to prevent any loss. Also, check for all dependencies, like NICs and public IPs, to ensure everything needed is included in the move
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