Why do some of my sites work on CloudFlare, but others do not. I have a settings problem

I have about 50 newspaper websites in my CloudFlare account. With this Coronavirus craziness, my servers are working HARD! So I need CloudFlare turned on, but… I have a big problem that nobody has solved to date. I’ll explain;

All of my sites are configured the same. All of my sites use the same software solution and template, and the same page rules. They’re hosted on 2 identical Amazon servers (with mod_cloudflare installed). Same same same.

My websites all have a staff interface, where the staff uploads stories and photos, processes payments, classified ads, etc. This staff interface uses sessions and IP security. (IP Security makes it so if someone’s IP changes, they lose their session then get sent to a 404 error etc.)

Anyways, some of my domains have a problem where they lose their session over and over, but only in the staff interface. (These URLs contain “cgi-bin” in them.) When this happens, sometimes I can’t even pull up the URL to log into the staff interface. It just gives me a cached 404 page… UNTIL I turn CloudFlare off, then it all works fine.

I even went so far as to ratchet my page rules waaay down to cache almost nothing. Here’s a screenshot of my Page Rules. http://www.unifiednews.com/page_rule_example.png

And yes, I have “Always Online” turned off.

Does anyone have any ideas? Or is anyone knowledgeable about their settings open to a quick Skype session to review my settings?

Thank you
Dan W.