While deploying do you get any error messages?
Check with these steps whether you are following them properly.
-Choose an existing policy in the BitLocker Management node. In the ribbon, select Deploy.
-Select a device collection as the target of the deployment.
-If you want the device to potentially encrypt or decrypt its drives at any time, select the option to Allow remediation outside the maintenance window. If the collection has any maintenance windows, it still remediates this BitLocker policy.
-Configure a Simple or Custom schedule. The client evaluates its compliance based on the settings specified in the schedule.
-Select OK to deploy the policy.
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