Add key to secure element fails

I’m trying to add a key to the secure element as described in However, it fails with the following error:

> ./build/dragon_buildext_mission/ --add-key fm-provider-public-key.pem --drone-address
INFO:root:Retrieving drone serial number
INFO:root:-> PI040450AA1K001871
INFO:root:Creating temporary APC user and authentication token
INFO:root:Generating challenge
INFO:root:Sending challenge to drone
INFO:root:Completing operation with drone response
ERROR:root:Exception occured: 403 Client Error: Forbidden for url:*(...removed encoded message...)*

Is it necessary to do anything else for that command to work?

I tried the command from a new setup/computer and I get the same result.
Is there any authorization from the Anafi AI necessary?