Failed to parse args: repos "..." does not exist

Hello! I recently installed volt to manage profiles between programming and basic file editing, but it seems something has gone wrong... I intend to enable a plugin (let's suppose I want vim-airline/vim-airline). I have verified this is a valid git URL and a plugin (via vim-plug), however, this is the error message I receive:

[ERROR] failed to parse args: repos 'github.com/vim-airline/vim-airline' does not exist