Users authenticated through command_line auth provider aren't given usernames

Configuration
1

I set up command line authentication against PAM using an application I wrote, which succeeds in authenticating users but when someone signs in using that authenticator the user account in Home Assistant has an empty username. Shouldn’t it be the same username that was authenticated?
Screenshot_20220221_131533

My config:

homeassistant:
  auth_providers:
    - type: trusted_networks
      trusted_networks:
        - 127.0.0.1/32
      trusted_users:
        127.0.0.1/32: f8dea2d52d3542659732c0f081c75ff9
      allow_bypass_login: true
    - type: command_line
      command: /config/ha-pam-authenticate
      meta: true
    - type: homeassistant