def remove_from_game(game_data, from_phone_number):
    """
    Remove a player from the game
    If roles have already been assigned, don't change anything and return None
    """
    if 'roles' in game_data:
        return None
    ind = game_data['numbers'].index(from_phone_number)
    del game_data['numbers'][ind]
    del game_data['names'][ind]
    return game_data