@Aran Billen, Thanks for posting in Q&A.
From your description, I know you want to enable BitLocker on your device but failed for some reasons.
To clarify this issue, please confirm and check something below.
1.Could you please confirm us do you want to silently enable BitLocker on your device or you just want to enable BitLocker on your device, because if you just enable BitLocker , you should manually enable it on targeted device if the policy deployed, if you want to silently enable it, there is some settings missing in your policy that may failed to encrypt the device, here is a link you can refer to re-configure the policy.
https://c7solutions.com/2023/11/enabling-bitlocker-in-silent-mode-using-the-settings-catalog
Non-official, just for reference.
2.Please check whether your device meet the requirement below.
Meanwhile, I notice the encryption readiness status of the device is "Ready" but the encryption status is "Not encrypted", it is possible that encryption isn't finished yet. Please run "manage-bde -status" command to confirm if it is encrypted on the device.
3.If you re-configure the policy and deploy it successfully, but the device still cannot encrypt, please check Event Viewer and Registry to see if the policy has been applied and if there exist some related information.
Please check above information, if there is any update, feel free to let me know.
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