Home / Frontpage not being cached

Hi, I have activated the cache plugin with basic settings

But I find that home page is not being cached by WP Optimize. Anyway to force WP Optimize to cache the home page?

Our settings are (the settings that are active)

Enable Page Caching
Serve cached pages to logged in users
Cache lifespan 12 hours
Gzip Enabled
Browser static file caching headers are currently enabled.

Minify is disabled (as enabling Minify seems to cause conflict with Modern Calendar Events)

Also when we generate cache, I see only when user visits a page, it creates a cache of that page. So is it not possible to pre generate cache for all pages on the site?

I am using the free version of your plugin.