Can't delete files and folders backup (MARS agent key lost)

Hello,

Hello, I've created a Files and Folders backup with MARS. Now I want to delete it but I've lost on-premise key and agent is uninstalled.

I tried PS from : https://docs.microsoft.com/en-us/azure/site-recovery/delete-vault

and changed security soft delete (https://docs.microsoft.com/en-us/azure/backup/backup-azure-security-feature-cloud#disabling-soft-delete)

Thank you

Patrick