When i click on the brand under specifications I would assume it would then show all products in the brand section (which we have already created) but its showing other products NOT in that brand,
Make sure that you have created one menu item of the type hikashop brands listing and that it works properly on its own. The system will then pick it up to generate the brand links on your product pages.
I checked your website and apparently you already have such menu item but the system is not picking it up.
It could be that either you have another menu item of that same type not configured properly, or that you have a view override of the view file "show_block_dimensions" from an old version where the brand link did take into account such brand menu item. So I would recommend to check that via the menu Display>Views.
