SEF URLs & routing

-- HikaShop version -- : 4.0.3
-- Joomla version -- : 3.9.2
-- PHP version -- : 7+
-- Browser(s) name and version -- : n/a
-- Error-message(debug-mod must be tuned on) -- : n/a

Hi,

I'm having a number of issues where URLs are able to be navigated that shouldn't be or aren't the primary URL to a product. If you see square brackets below it's just where I have swapped out the real parts of the URL with a description of what is there.

For example;
- adding "/product/listing" to the end of a URL, shouldn't be navigatable but it is and goes to page with no information or products.
- /category_pathway-12 getting added to the end of product URLs
- price-list/[brand-menu]/product/[different-brand-product]/category_pathway-44
- price-list/[brand]-repairs/[product]-repairs/[product]-repairs - the last part of the URL is duplicated incorrectly and takes you to a page with a list of brand names.
and many many many more.

These URLs are being recorded by the auto-crawl mode of RSSEO and are navigatable. So as I don't understand how the routing system works I'd like to know how I can avoid getting all these wired URLs.

I do understand I can use the canonical feature for products to help direct Google to the right place but some of these are allowing access to pages that lack any real information and just basically have a header and footer. Also, yes the 404 error page does work correctly for pages that you can't navigate to, outside of Hikashop. But it seems that something is allowing navigation to these URLs within Hikashop.

Thanks for your help.