When you try suspend BitLocker via Task Sequence step it fails. On checking smsts.log you find out the below errors

Even if you try to run manage-bde -protectors -disable c: in an elevated command prompt it fails with “Invalid Namespace” error.

Cause
This problem occurs if the Bitlocker WMI class (win32_encryptablevolume) is not registered or missing registration.

Resolution
To resolve this problem, you have to re-register the BitLocker WMI (win32_encryptablevolume) class.

Open an elevated command prompt and type the following command:
mofcomp.exe c:\windows\system32\wbem\win32_encryptablevolume.mof

If the file successfully compiles you will receive the following message:
Microsoft (R) MOF Compiler Version 6.1.7600.16385
Copyright (c) Microsoft Corp. 1997-2006. All rights reserved.
Parsing MOF file: win32_encryptablevolume.mof
MOF file has been successfully parsed
Storing data in the repository…
Done!

Now re-run the task sequence and it should successfully suspend and enable BitLocker.