Shipping method not showing on invoice

-- HikaShop version -- : 3.4.1
-- Joomla version -- : 3.8.10
-- PHP version -- : 5.7
-- Browser(s) name and version -- : firefox
-- Error-message(debug-mod must be tuned on) -- : Shipping method :
Notice: Undefined property: plgHikashopAttachinvoice::$order in
xxx/plugins/hikashop/attachinvoice/attachinvoice/invoi coen. plinhep 346
Notice: Trying to get property of non-object in
xxx/plugins/hikashop/attachinvoice/attachinvoice/invoi coen. plinhep 346
Warning: implode(): Invalid arguments passed in
xxx/plugins/hikashop/attachinvoice/attachinvoice/invoi coen. plinhep 346

this is what shows at bottom of our invoices

Shipping method :
Notice: Undefined property: plgHikashopAttachinvoice::$order in
xxx/public_html/plugins/hikashop/attachinvoice/attachinvoice/invoi coen. plinhep 346
Notice: Trying to get property of non-object in
xxx/public_html/plugins/hikashop/attachinvoice/attachinvoice/invoi coen. plinhep 346
Warning: implode(): Invalid arguments passed in
xxx/public_html/plugins/hikashop/attachinvoice/attachinvoice/invoi coen. plinhep 346

If i turn off error reporting they display ok, but wanted to check these errors.

Hello,

Can you download the last version of the Attach invoice plugin through our website, install it and test it again ?

Thank you.

I cannot find any plugins to download on the website. I am logged in and it does not show in my downloads or in the download area, please help me find it.
\
\EDIT I did find it but i have to pay for it? it is not part of my business subscription? I don't recall paying for it previously. Can i just fix the code? the error is in the implode

if (!empty($pluginsShipping)){
echo JText::_('HIKASHOP_SHIPPING_METHOD').' : ';
if(is_string($order->order_shipping_method)) {
if(strpos($order->order_shipping_id, '-') !== false)
echo $shippingClass->getShippingName($order->order_shipping_method, $order->order_shipping_id);
else
echo $pluginsShipping->getName($order->order_shipping_method, $order->order_shipping_id);
}else{
echo implode(', ', $this->order->order_shipping_method);
}
echo '<br/>';
}

Hi,

That plugin is sold here and has never been part of HikaShop itself:
www.hikashop.com/marketplace/product/18-plugin-pdf.html
So if you're using it, we assume that you already purchased it (and you did, I checked).
So you already have access to it. Go in the menu My account>My orders, click on your order C3U4N1F37 and there you'll have a download link for it. It's the same link you used the first time you downloaded it.

The fix is already included there. Now if you want to patch the code without updating the plugin, you can just change the line:
echo implode(', ', $this->order->order_shipping_method);
to:
echo implode(', ', $order->order_shipping_method);
Mohamed just wanted to give you a simpler answer for you to apply.

I downloaded that plugin and installed. It still gave error, so i manually edited the file with your code and that worked. Thank you!