It takes some time for the rich snippets to appear after changing an SEO plugin/rich snippet plugin. I have compared the cache information on the links that are showing the ratings and the ones that are not when doing a search and it is clear that the affected pages have not been updated on the cache.
Here is an example of the same link: Not showing star rating
Showing star ratings
Please allow some time for the Google cache to be updated.
Also, I want to add that
I have performed speed optimization on site by my friend. He have used some cache plugins for optimizing the site.
Star ratings disappeared after that speed optimization.
So, I want to know if it is due to Speed Optimization?