Critical CSS

Hey,

I have been using autoptimize plugin for sometimes for my website https://www.almiriatechstore.co.ke/ and have been happy on how the mimify Javascript. I recently subscribed to Improve first paint times by removing render-blocking CSS by buying the API but my speed never improved. In contrast the speed went down. What might be the issue

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