Hi,
With HikaShop only, without 4SEF and 4SEO, I would recommend to simply enter the URL you want in the "canonical URL" of the products.
Then, ask google to unindex / reindex these wrong URLs and everything should be good again.
With 4SEO and 4SEF, I'm not sure. It might depend on how they are configured.
Having correct canonical URLs in the products is good anyways, but maybe there are other things that need to be done in 4SEO or 4SEF.
I would recommend checking with their developer's support what they recommend.