How do I remove ANF volume assignments from the Backup Vault?

Hi Robert Garlington,
Welcome to Microsoft Q&A Forum, Thank you for posting your query here!,
Based on your scenario there are few possible causes:

To remove the backup policy settings for volume 3 and delete the backup from the vault, you can follow these steps:

1. Enable the backup operation for each volume that you want to remove from the backup policy. This will delete all backups stored in Azure storage for that volume. You can do this by selecting the specific volume you want to stop and the backup assignment, selecting Configure, toggling the Enabled setting to Off, typing a volume name to confirm, and pressing OK
2. Remove the volume assignment from the backup policy. You can do this by going to Backups, selecting Backup Policies, clicking the three dots (``) to the right of the backup policy, clicking Edit, and removing the volume assignments from the policy
3. Delete the backup from the vault. You can do this by going to Backups, selecting Backups, selecting the backup you want to delete, clicking the three dots (``) to the right of the backup, and clicking Delete from the Action menu

*Please note that backup deletions cannot be undone, so make sure you have a backup of your data before continuing.

For more information:
https://video2.skills-academy.com/en-us/azure/azure-netapp-files/backup-configure-policy-based· 

Please let us know if you have any further queries. I’m happy to assist you further.

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