Codeigniter library to create request send message via send.wanotif.com API

Lib_whatsapp.php

<?php

defined('BASEPATH') or exit('No direct script access allowed');

class Lib_whatsapp
{
    protected $CI;

    function __construct()
    {
        $this->CI =& get_instance();
        $this->CI->load->config('whatsapp');
    }

    public function send_whatsapp($api, $number, $message) {
        if (DEMO) {
            $this->session->set_flashdata('error', 'Whatsapp are disabled in demo.');
            return false;
        }

        $date = date('Y-m-d H:i:s');

        try {
            $client = new \GuzzleHttp\Client();
            $wa_base_url = $this->CI->config->item('wa_base_url');
            $response = $client->post("$wa_base_url/ssem_api/send_wa_api",
                [
                    'form_params' => [
                        'api_key'      => $api,
                        'mobile'       => $number,
                        'reference_id' => 'wanotif', // you can change with your app name
                        'message'      => $message
                    ]
                ]
            );

            return true;
        } catch (\Exception $e) {
            $this->set_error($e->getMessage());
            return false;
        }
    }
}