Custom field on thank you page

Hello,
i am strugling for hours on simple task. Via function/hook i created custom field on checkout page for mobile phone.

// Hook in
add_filter( 'woocommerce_checkout_fields' , 'custom_override_checkout_fields' );

// Our hooked in function - $fields is passed via the filter!
function custom_override_checkout_fields( $fields ) {
     $fields['billing']['shipping_phone'] = array(
        'label'     => __('Phone Iphone', 'woocommerce'),
    'placeholder'   => _x('Phone', 'placeholder', 'woocommerce'),
    'required'  => false,
    'class'     => array('form-row-wide'),
    'clear'     => true
     );

     return $fields;
}

now i open thankyou template and add

 <? echo '<p><strong>'.__('Phone From Checkout Form').':</strong> ' . get_post_meta( $order->id, '_shipping_phone', true ) . '</p>';  ?>

But i dont get value from shipping phone ?? just get that strong text printed adn thats it.