Products not displaying under their categories

-- url of the page with the problem -- : better4u.co.uk/index.php?option=com_hika...l-roll-on&Itemid=210
-- HikaShop version -- : HikaShop Business: 2.3.4
-- Joomla version -- : 2.5.11
-- Browser(s) name and version -- : Firefox

No matter what I try, I can not get some of the products to list under their category. On my website better4u.co.uk there is a menu item called 'Our Products' which links to the HikaShop » Categories listing. When this opens, it displays the 4 different categories listed, but when I click on to the 50ml Roll-on Deodorants, I have either 'Moisturisers' or 'Random products' load. It will not load the items in that category.
Yet if I access the categories from the HikaShop menu on the left, then click on any of the individual categories, the right items are displayed.
This problem has been bugging me for weeks, so any suggestions would be greatly appreciated.

I logged into your demo site and copied the example exactly the way it was there and still no luck. I also followed the instructions from your link, again without success. Since then, I have rearranged the menu items to suit the site by changing the menu item to view all products with the individual categories on the side menu, and that works as I want it, so at the moment, this is not a main concern.
I am still not 100% happy, but I am willing to let it ride for now.
I am still finding my way around the program, so I am willing to concede that it may still be down to my 'inexperience' with the software. I am going to build a test site on my localhost and spend some time practising, and hopefully I will resolve the mentioned issues and a few more I have before posting more problems on this forum.
I thank you for your help anyway.