Hello,
Thanks !
I was able to check your configuration and reproduce it in a local website.
Please edit the file "administrator/components/com_hikamarket/classes/cart.php" and replace
$v = isset($product_vendors[ $pid ]) ? (int)$product_vendors[ $pid ]->product_vendor_id : 0;
if($v == 0 && !empty(self::$zone_id))
$v = self::$vendor_id;
By
$v = isset($product_vendors[ $pid ]) ? (int)$product_vendors[ $pid ]->product_vendor_id : 0;
if($v == 0 && !empty($p['data']) && !empty($p['data']->product_parent_id))
$v = (int)$product_vendors[ (int)$p['data']->product_parent_id ]->product_vendor_id;
if($v == 0 && !empty(self::$zone_id))
$v = self::$vendor_id;
And it will fix the issue.
In our side the patch will be integrate into HikaMarket next release ; and maybe in the current package as hot-fix.
Regards,