I had the same problem on my machine and found the following solution:
The group policy of your machine needs to be changed to allow for bitlocker to run without TPM enabled.
To do this, click on the the
Windows button and hit
R to run to start the run command.
gpedit.msc into the run command box and hit enter.
Navigate to the following:
Local Computer Policy > Computer Configuration > Administrative Templates > Windows Components > BitLocker Drive Encryption > Operating System Drives in the left pane.
Double-click the “Require additional authentication at startup” option.
Select “Enabled” at the top of the window, and ensure the “Allow BitLocker without a compatible TPM" checkbox is enabled here.