Ionic cordova

bonjour,dans un projet d'application hybride ionic cordova j'ai une problème lorsque j'ajoute la platform android dans le projet et voila le massage qui m'affiche,j'ai besoin d'aide merci en attendant votre reponse.

Microsoft Windows [version 6.1.7600]
Copyright (c) 2009 Microsoft Corporation. Tous droits réservés.

C:\ws\IONIC\MyApp>ionic add platform android
[ERROR] Unable to find command: add platform android

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|_|\___/|_| |_|_|\___| CLI 3.3.0


Usage:

$ ionic <command> [--help] [--verbose] [--quiet] [<args>] [options]
$ ionic [--confirm] [--no-interactive] [--yarn] [--no-timeout]

Global Commands:

docs ..................... Open the Ionic documentation website
info ..................... Print system/environment info
login .................... Login with your Ionic ID
signup ................... Create an Ionic account
start .................... Create a new project
telemetry ................ Opt in and out of telemetry

Project Commands:

generate ................. Generate pipes, components, pages, directives, providers, and tabs (ionic-angular >=
3.0.0) (alias: g)
link ..................... Connect your local app to Ionic
serve .................... Start a local dev server for app dev/testing
upload ................... Upload a new snapshot of your app
package build ............ Start a package build
package download ......... Download your packaged app
package info ............. Get info about a build
package list ............. List your cloud builds


C:\ws\IONIC\MyApp>