Hi,
In the file "administrator/components/com_hikamarket/classes/plugin.php" you will find a function named "parseData".
In that function, you will find twice the content
And you need to replace it by
unset($d);
$data = implode(',', $data);
break;
It will force the data to be a string so we will be sure that the data will be stored in the database.
I'll investigate in order to understand why HikaMarket should now need to perform that serialization and I will update the HikaMarket packages as soon as possible.
Regards,