Hi,
After sending my message I saw that there was a message in the contact box.
I checked your website and you have an issue with the loading of the "product options" in order.
The fact that you didn't have that issue in every order is because the problem was just when you had "product options"
That problem is already fix for the next release (we perform a refactoring of the order edition system) so for the moment I just applied a patch in the view in order to skip a product to be displayed twice.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.