Symantec Whole Disk Encryption - Admin Passphrase

I'm running Symantec Whole Disk Encryption 10.3 on a Linux machine.

I setup a user with password recovery questions.

According to documentation (10.2) I can run the comment recovery-change-passphrase with an answers file to change the passphrase

pgpwde --recovery-change-passphrase --user "Alice Cameron" --disk 0 --new-passphrase 'Bilbo%Baggins$Underhill' --answers-file
"C:\pgpwde\answers.txt"

But when I run it I get

No passphrase specified
No admin-passphrase specified
No authentication credentials found. Valid credentials for this operation are: 
  User passphrase, 
  admin passphrase, 
  recovery token

"operation change user self recovery user's passphrase failed: Error code -12000: pad parameters"

So the questions are

1. Shouldn't it work with just the answers file?

2. I noticed that I can specify an admin passphrase when I add the user which's passphrase I now want to recover.
    The recovery than works with that admin passphrase. But how can I change this admin passphrase?