Horizon theme appending product URLs

Switched to Horizon theme in Shopify from Debut theme. Horizon theme appended all product URLs. New URLs are not getting indexed on Google and not showing in search results. Google has cached product details from Debut theme and is continuing with the same since it is the clean URL whereas the Horizon appended URL is with variant addition. How to fix this issue in Shopify?

Website: amodaromas.com

This is normal.
There is nothing to fix.

While collection page link may look like this
https://amodaromas.com/products/celestial-scent?variant=41154056945816,
when visitors arrive on this page it has
<link rel="canonical" href="https://amodaromas.com/products/celestial-scent">

So basically, it says – “this URL with variant parameter points to the same page as before, without the variant parameter”

Now, google sees that this URL without parameter is already indexed and there is no need to index the long one, just keep the canonical one indexed…

It is not that old URLs are “cached”, they are current valid ULRs Google has in its index.

more

Well, your crawl budget got stretched with those extra URLs and you will see diagnostic like “Crawled - currently not indexed” or “Alternate page with proper canonical tag”, but these are not errors as well.

You could avoid this if you’ve modified the theme code, but there are drawbacks too.
Since Google has already learned about those URLs it would not “unlearn” them because those are valid URLs.

The issue is we have changed the product description and optimised it for Seo but the new product page is nowhere to be found on google.

Screenshots help a lot to let people see what you’re seeing. What does it say when you run live test on a certain page? Etc. Use the tools to guide you to a conclusion.

Google Search Console is a very simple tool, but It’s not fast.. sometimes you just gotta let it do its thing for a while.