Hey @swa,
really sorry for the late reply.
It looks like you're attempting to use the new CLI commands on Mattermost 3.2. You can either
a) Upgrade to Mattermost 3.6 to use the new CLI tools
b) Use the legacy CLI commands which can be found here
I've also submitted a pull request proposing we add the old CLI commands to the doc for those running on older Mattermost deployments https://github.com/mattermost/docs/pull/949