Hi,
The link in your checkout cart is a link which is pointed directly to the variant you choose.
In the test I made, it was the variant "p5i01".
So instead of having a link to "/fitted-wardrobes/product/imperial-wardrobe-width-151cm"
I got a link to "/fitted-wardrobes/product/p5i01" ; link which does not work properly as you know.
So, I think that it will be interesting to have more details about the "canonical url" which is set for this variant.
Maybe a modification will be required in HikaShop cart in order to create a link to the parent product and not the product variant ; it could solve your issues like yours.
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.