Hi,
You have in your orders some with invalid shipping methods, so the import of the shipping plugin failed.
Please edit the file "components/com_hikamarket/views/ordermarket/view.html.php" and replace
	$shippingMethod = hikamarket::import('hikashopshipping', $shipping_method);
	$methods = $shippingMethod->shippingMethods($shipping);
	$shipping_name = $shipping->shipping_name.' - '.$methods[$shipping_id];By
	$shippingMethod = hikamarket::import('hikashopshipping', $shipping_method);
	$methods = array();
	if(!empty($shippingMethod))
		$methods = $shippingMethod->shippingMethods($shipping);
	if(isset($methods[$shipping_id]))
		$shipping_name = $shipping->shipping_name.' - '.$methods[$shipping_id];It will avoid such fatal error (and we will include that patch in the next release).
Regards,