Display customer cancelled orders count in Woocommerce Admin Edit Orders pages

You need to target the Customer ID from the current order. It can be done in a much simpler way.

You should try this:

add_action( 'woocommerce_admin_order_data_after_order_details', 'get_specific_customer_orders', 10, 1 );function get_specific_customer_orders( $order ) {    $customer_orders = get_posts( array(        'numberposts' => -1,        'meta_key'    => '_customer_user',        'meta_value'  => $order->get_customer_id(),        'post_type'   => 'shop_order',        'post_status' => array('wc-cancelled'),    ) );    $orders_count = '<strong style="color:#ca4a1f">' . count($customer_orders) . '</strong>';    echo'<br clear="all">    <p>' . __( 'Cancelled orders count: ' ) . $orders_count . '</p>';}

Code goes in function.php file of your active child theme (or active theme) or in any plugin file.

Tested and works.

I used this for my project:
use

get_current_user_id()

instead of

$order->get_customer_id()

add_shortcode( 'geo-get-customer-orders', 'geo_get_customer_orders' );function geo_get_customer_orders() {    global $order;    $customer_orders = get_posts( array(        'numberposts' => -1,        'meta_key'    => '_customer_user',        'meta_value'  => get_current_user_id(),        'post_type'   => 'shop_order',        'post_status' => array('wc-completed'),    ) );    echo count($customer_orders);}

finally use this shortcode:

[geo-get-customer-orders]