@Itay Menashe Thank you for reaching out to us!
The detailed process to delete Azure recovery service vault (RSV) is documented here - https://learn.microsoft.com/en-us/azure/backup/backup-azure-delete-vault
Deleting the backed up resources is not enough to delete RSV, you need to delete the underlying resources as well.
Just wanted to specifically highlight on the process to delete MARS agent backup - https://learn.microsoft.com/en-us/azure/backup/backup-azure-delete-vault#delete-backup-items-from-the-mars-management-console the process is little different from other protected backup instances.
Hope this helps. Let us know if you need further assistance in this matter!
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