First, when did you add the code ? It can take upwards of 6 weeks or longer to actually see "Starred" results in the serps.
The other issues you are facing is this
When I searched "STRING OF PEARLS SENECIO ROWLEYANUS", your H1 tag
( I used google incognito to search )
This page is the first results:
https://succulentsbox.com/blogs/blog/how-to-care-for-string-of-pearls
This page provides a much better answer according to Google's search algo's. Your page that you're trying to promote doesn't show up in the serps at all. Try adding an internal link from your blog page to the product page. It may help you.