Reviews not Synced/updating on Website

I have been using this plugin for a while and it’s great! However, I came to know that the reviews aren’t synced properly. I have more reviews on the CUSREV site and some missing reviews on the WP backend and live site. At WP backend shows a review reminder sent but the customer has already left a review and is visible on CUSREV site. What would be the cause of missing/not properly synced reviews?
Check this page it shows 4 reviews https://www.cusrev.com/reviews/woomen.pk/p/p-21288
but on the product page, it only shows two, and the most recent one is also missing.

The page I need help with: [log in to see the link]