Payment method option is not appearing on the WooCommerce checkout page

I'm attempting to integrate a custom payment method into WooCommerce. I've successfully added the backend option to enable or disable it, but I can't seem to get the custom payment method to appear on the checkout page. I've attached a screenshot of both my admin panel and the frontend checkout page for your reference. Please take a look as I've attempted various solutions but have been unable to resolve the issue.

<?php
/*
Plugin Name: SecureNet Payment Gateway
Version: 1.0
Description: Add SecureNet Payment as a payment option in WooCommerce.
Author: Your Name
*/

// Define the custom payment gateway class
function custom_payment_gateway_init() {
class Custom_Payment_Gateway extends WC_Payment_Gateway {
public function __construct() {
$this->id = 'custom_payment_gateway'; // Unique ID for your payment gateway
$this->method_title = 'Custom Payment Gateway';
$this->method_description = 'Add a custom description here.';
$this->has_fields = true;
$this->init_form_fields();
$this->init_settings();
$this->title = $this->get_option('title');
$this->description = $this->get_option('description');
// Add more settings here
// ...
add_action('woocommerce_update_options_payment_gateways_' . $this->id, array($this, 'process_admin_options'));
}

public function init_form_fields() {
$this->form_fields = array(
'title' => array(
'title' => __('Title', 'woocommerce'),
'type' => 'text',
'description' => __('This controls the title displayed during checkout.', 'woocommerce'),
'default' => __('Custom Payment Gateway', 'woocommerce'),
'desc_tip' => true,
),
'description' => array(
'title' => __('Description', 'woocommerce'),
'type' => 'textarea',
'description' => __('This controls the description displayed during checkout.', 'woocommerce'),
'default' => __('Pay using Custom Payment Gateway', 'woocommerce'),
'desc_tip' => true,
),
// Add more fields here
// ...
);
}

public function process_payment($order_id) {
// Handle payment processing logic here
// Connect to your payment gateway API, redirect to payment page, and confirm payment
// Implement error handling and status updates
// ...

return array(
'result' => 'success', // or 'failure' for unsuccessful payments
'redirect' => $redirect_url, // URL to redirect the customer for payment
);
}

public function payment_fields() {
// Display payment fields such as credit card info or other required info
// ...

// Example: You can use WooCommerce form fields to capture payment information
echo '<div id="custom-payment-gateway-form">';
// Display fields here
echo '</div>';
}

public function validate_fields() {
// Validate payment fields submitted by the customer
// Implement validation logic
// ...

// Example validation:
if (empty($_POST['custom_field'])) {
wc_add_notice(__('Custom field is required.', 'woocommerce'), 'error');
}
}
}
}

// Hook the custom_payment_gateway_init function to plugins_loaded action
add_action('plugins_loaded', 'custom_payment_gateway_init');

// Add custom payment gateway to available payment gateways in checkout
add_filter('woocommerce_payment_gateways', 'add_custom_payment_gateway');
function add_custom_payment_gateway($gateways) {
$gateways[] = 'Custom_Payment_Gateway';
return $gateways;
}