Engintron Caching Issue

I have a WordPress site and readers have been complaining that newly published posts cannot be seen on the category archive pages. I didn't think there was an issue, because everything looked fine for me. Turns out, it only looked okay for me because I was signed in. Once I viewed in Incognito (or signed out), I was able to duplicate the issue. I assumed it was a Cloudflare caching issue and set up some page rules, but that didn't work. I purged the cache, still didn't work. Cleared browser cache, nothing. What was weird, on mobile devices - everything worked normally. I could only seem to replicate the issue on desktop devices. I then decided to 'Purge cache & temp files' in Engintron - and it fixed the issue, but only for posts up until that point. I'm having to clear the cache every day in order to show newly published posts to our readers. It's a very large website, so purging also slows the server down for several minutes - so I'd like to find a permanent fix. Any ideas?