woocommerce third party shipping methods - woocommerce

Question

I have created woocommerce plugin which gets shipping rates from third party URL(my web site) and displays it on the checkout page. when I click on one of shipping method it also calculates correct shipping rates, but when I again refresh checkout page my selected shipping option gets lost and I have to select again. also, my custom shipping option does not reach to order after a successful order.
In below Screenshot, I pass Suburb and Postcode, and I get all rates i desire, when i click on one of shipping method it also calculates correct a shipping rates
After Click on Place Order, it takes first shipping method which is a flat rate: $5, please see below screenshot
Here is my Plugin please have a look and guide me where I am going wrong.
<?php
/**
* Plugin Name: Iconsignit Shipping
* Plugin URI: http://Iconsignit.com.au
* Description: Iconsignit Shipping Method for WooCommerce
* Version: 1.0.0
* Author: Jaimin prajapati
* Author URI: http://www.webbrainstechnologies.com
* License: GPL-3.0+
* License URI: http://www.gnu.org/licenses/gpl-3.0.html
* Domain Path: /
* Text Domain: Iconsignit
*/
if (!defined('WPINC')) {
die;
}
/*
* Check if WooCommerce is active
*/
if (in_array('woocommerce/woocommerce.php', apply_filters('active_plugins', get_option('active_plugins')))) {
function iconsignit_shipping_method()
{
if (!class_exists('Iconsignit_Shipping_Method')) {
class Iconsignit_Shipping_Method extends WC_Shipping_Method
{
/**
* Constructor for your shipping class
*
* #access public
* #return void
*/
public function __construct($instance_id = 0)
{
$this->id = 'iconsignit';
$this->instance_id = absint($instance_id);
$this->method_title = __('Iconsignit Shipping', 'iconsignit');
$this->method_description = __('Custom Shipping Method for iconsignit', 'iconsignit');
$this->init();
$this->enabled = isset($this->settings['enabled']) ? $this->settings['enabled'] : 'yes';
$this->title = isset($this->settings['title']) ? $this->settings['title'] : __('Iconsignit Shipping', 'iconsignit');
}
/**
* Init your settings
*
* #access public
* #return void
*/
function init()
{
// Load the settings API
$this->init_form_fields();
$this->init_settings();
// Save settings in admin if you have any defined
add_action('woocommerce_update_options_shipping_' . $this->id, array($this, 'process_admin_options'));
}
/**
* Define settings field for this shipping
* #return void
*/
function init_form_fields()
{
// We will add our settings here
$this->form_fields = array(
'ApiToken' => array(
'title' => __('Api Token', 'iconsignit-integration-demo'),
'type' => 'text',
'description' => __('Enter with your API Key. You can find this in "User Profile" drop-down (top right corner) > API Keys.', 'iconsignit-integration-demo'),
'desc_tip' => true,
'default' => '',
),
'ApiUrl' => array(
'title' => __('Api Url', 'iconsignit-integration-demo'),
'type' => 'text',
'default' => '',
'desc_tip' => true,
'description' => __('Website URL', 'iconsignit-integration-demo'),
),
'ConnectIconsignUrl' => array(
'title' => __('Iconsignit Url', 'iconsignit-integration-demo'),
'type' => 'text',
'default' => '',
'desc_tip' => true,
'description' => __('Url from where all shipping rates will come', 'iconsignit-integration-demo'),
),
);
}
/**
* This function is used to calculate the shipping cost. Within this function we can check for weights, dimensions and other parameters.
*
* #access public
* #param mixed $package
* #return void
*/
public function calculate_shipping($package = array())
{
// We will add the cost, rate and logics in here
$item = array();
$count = 0;
foreach ($package['contents'] as $item_id => $values) {
$item[$count]['item_qty'] = $values['quantity'];
$item[$count]['item_length'] = $values['data']->get_length();
$item[$count]['item_width'] = $values['data']->get_width();
$item[$count]['item_height'] = $values['data']->get_height();
$item[$count]['item_weight'] = $values['data']->get_weight();
$item[$count]['item_palletised'] = 0;
$count++;
}
$country = $_POST['s_country'];
$state = $_POST['s_state'];
$postcode = $_POST['s_postcode'];
$city = $_POST['s_city'];
$address = $_POST['s_address'];
$address_2 = $_POST['s_address_2'];
$isCredentials = get_option('woocommerce_iconsignit_settings');
$data = array('ApiUrl' => $isCredentials['ApiUrl'], 'ApiToken' => $isCredentials['ApiToken'], 'DeliveryTown' => $city, 'DeliveryPostcode' => $postcode, 'Items' => $item);
$isResponse = Requests::post($isCredentials['ConnectIconsignUrl'].'/api/getconsignrate', array(), $data);
$resp = json_decode($isResponse->body, true);
$counter = 1;
foreach ($resp['result'] as $key => $res) {
$rate = array(
'id' => $res['QuoteRateID'],//$this->id,
'label' => $res['carrier_nm'] . "-(" . $res['service_nm'] . ")",
'cost' => $res['total_charge'],
'calc_tax' => 'per_item',
);
$this->add_rate($rate);
$counter++;
}
}
}
}
}
add_action('woocommerce_shipping_init', 'iconsignit_shipping_method');
function add_iconsignit_shipping_method($methods)
{
$methods[] = 'Iconsignit_Shipping_Method';
return $methods;
}
add_filter('woocommerce_shipping_methods', 'add_iconsignit_shipping_method');
}

Answer 1

problem is solved the problem was in $this->id, it should have to be unique.