Hello @HARRAG Achraf [ECM] (EXT) ,
Welcome to Microsoft Q&A community forums!
Apologies for delay in response to your query. Much appreciate your time and patience.
Reg: your query: You may want to modify protection instead of enabling protection as I assume you already have the VM protected currently and excluded two of the disks.
You can either reconfigure disk inclusion settings using modify protection - https://learn.microsoft.com/en-us/azure/backup/selective-disk-backup-restore#modify-protection-for-already-backed-up-vms-with-azure-cli
OR just remove disk exclusion setting all together - https://learn.microsoft.com/en-us/azure/backup/selective-disk-backup-restore#remove-disk-exclusion-settings-and-get-protected-item-with-azure-cli
Hope this helps!
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