Hello @Dharshinika-FT Thank you for reaching out to us at Microsoft Q&A forum. Happy to assist!
I see that you want to change the recovery services vault for your azure VM but unable to do so. This is by design. You cannot protect a VM which is already registered/protected to an existing vault. Because the resource ID of the VM protected is associated with the vault. In order to re-protect the VM you need to un-protect the VM from existing vault that releases the resources ID of the VM which enables you to re-protect the VM in question with new recovery services vault. Regarding data that was backed up for that VM can be retained. However, you'll need to pay to keep the recovery points in the vault. For details refer to - https://video2.skills-academy.com/en-us/azure/backup/backup-azure-manage-vms#stop-protecting-a-vm
Reference article to delete recovery services vault https://video2.skills-academy.com/en-us/azure/backup/backup-azure-delete-vault?tabs=portal
Hope this helps. Please reply if need further assistance in this matter!
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