Unable to install driver

[claretnnamocha]

i tried to install the driver using the command
composer require botman/driver-google-assistant

and this is the error i encountered

[InvalidArgumentException]
Could not find a version of package botman/driver-google-assistant matching your
tability (stable). Require it with an explicit version constraint allowing its de
bility.

require [--dev] [--prefer-source] [--prefer-dist] [--no-progress] [--no-suggest] [-[--no-scripts] [--update-no-dev] [--update-with-dependencies] [--update-with-all-de[--ignore-platform-reqs] [--prefer-stable] [--prefer-lowest] [--sort-packages] [-o|utoloader] [-a|--classmap-authoritative] [--apcu-autoloader] [--] []...

what should i do?