PHP Codeigniter - Upload file to Dropbox via HTTPS always empty

I'm trying to upload file using Kunnu Dropbox API. It works really well in localhost. But, when I try to upload from live server, it always upload empty file. What am i missing ?

Here is the code to upload :

$pathToLocalFile = base_url() .  "\\public\\dropbox_file\\" . $data['upload_data']['file_name'];$dropBox = $this->load->library("DropBox_lib");$drop_obj = new DropBox_lib();$drop_obj->set_mode_file(1);$drop_obj->set_drop_file($pathToLocalFile);
$drop_n = $drop_obj->drop_object;
$file = $drop_n->simpleUpload($drop_obj->drop_file, $path_f . "/" . $data['upload_data']['file_name'], ['autorename' => true]);

Here is the Library of Dropbox_lib.php

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed'); 

use Kunnu\Dropbox\Dropbox;
use Kunnu\Dropbox\DropboxApp;
use Kunnu\Dropbox\DropboxFile;

class DropBox_lib{
    public $drop_object;
    public $drop_file;
    public $drop_mode;
    
    public function __construct()
    {
        require_once APPPATH.'third_party/DropBox/vendor/autoload.php';

        //Configure Dropbox Application
        $app = new DropboxApp("xxxxxxxxxxxxxxxxx", "yyyyyyyyyyyyyyyyy", "zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz");

        //Configure Dropbox service
        $this->drop_object = new Dropbox($app);
    }

    public function set_mode_file($mode){
        if($mode == 1){
            $mode = DropboxFile::MODE_READ;
            $this->drop_mode = $mode;
        }else{
            $mode = DropboxFile::MODE_READ;
            $this->drop_mode = $mode;
        }
    }

    public function set_drop_file($pathlocal){
        $dropboxFile = new DropboxFile($pathlocal, $this->drop_mode);
        $this->drop_file = $dropboxFile;
    }
}

?>

The same codes work really well on localhost.

I think the problem is http request with SSL. Because my localhost is using http, while the live server using https