@Fernando,Thanks for posting in Q&A.
From your description, I know that there are some conflicts in BitLocker policy settings.
To narrow down the conflict, please provide us some information.
1.Could you provide how you configure BitLocker policy and BitLocker configurations? Check if there is other BitLocker policy assigned to the target device or if there is Security Baseline assigned to target device.
2.Go to the device and check if there exist related error in MDM agent event log. Location: Right-click on Start Menu > Event Viewer > Applications and Service Logs > Microsoft > Windows > DeviceManagement-Enterprise-Diagnostics-Provider > Admin
3.Go to the device and check if there exist related error in BitLocker-API management event log. Location: Right-click on Start Menu > Event Viewer > Applications and Service Logs > Microsoft > Windows > BitLocker-API
Thanks for your kind understanding.
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