Display var_dump data in woocommerce checkout Hook

I have this code want to display var_dump data in function Hook

But it is not showing on checkout page . After Checkout Button Click

add_action( ‘woocommerce_checkout_order_processed’, ‘update_withorder’, 10, 3);

function update_map_withorder ( $order_id, $posted_data, $order )
{
var_dump($order);
exit;
}

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