Hi,
On your live auctions listing the link to that car already points to /cars-live-auctions/makes/jaguar/jaguar15 (because you set that as the item's Canonical URL and you have "Force canonical URLs on listings" on), but opening it returns a 404. That is the key point: the Canonical URL field only changes the address displayed in the listing and the <link rel="canonical"> SEO tag, it does not create a working route, so the address itself leads nowhere.
Why it 404s on your site: /cars-live-auctions is your HikaShop live auctions listing, but /cars-live-auctions/makes and /cars-live-auctions/makes/jaguar are Joomla content pages (the "Makes" page and the "Jaguar 2026" article). The URL path is decided by your Joomla menu tree, and there is simply no menu item or route below the Jaguar article for jaguar15, so nothing resolves it.
The clean way to get a working URL at that exact path is to create the menu item for it. A couple of options:
1) Create a HikaShop "Product page" menu item for that auction and place it, in the menu tree, as a child of your "Jaguar 2026" article menu item, then set the menu item alias to jaguar15. Joomla will then own /cars-live-auctions/makes/jaguar/jaguar15 as a real menu item that displays the product, so it opens correctly. This keeps your Jaguar article as it is. The only thing to keep in mind is that this is one menu item per auction, which is fine for a few highlighted cars but heavy if you want it for every auction.
2) Or create a menu item alias (or a URL menu item) at that same spot under the Jaguar article, pointing to the auction's real product page URL. Same resulting address, it just forwards to the existing product page instead of being a second product menu item.
3) If you want this automatically for every auction without creating a menu item each time, the alternative is to build "Makes" and "Jaguar" as HikaShop categories rather than Joomla articles, and assign the auctions to them. HikaShop then generates the nested URL for every item on its own, and with "Remove products and categories id in URLs" set to Yes it produces exactly /cars-live-auctions/makes/jaguar/jaguar15. The trade-off is that those manufacturer pages become HikaShop category pages instead of Joomla articles, since a given path can only be owned by one component.
In all cases, do not rely on the Canonical URL field for this, it is an SEO pointer, not a routing or redirect tool.