When Cloudflare is on, errors on office

finally installed my nexcloud on vps via Hestia control panel.

Having a couple of problems:

  1. when I run CloudFlare, I get errors from office, that can’t create new doc… when I pause on CloudFlare my domain works fine.
  2. connected my mobile. But, when I try to upload something, getting error: “malformed server configuration”

Ubuntu 20.04 up to date
4GB ram
Nextcloud installed via Hestia

I’m very new to NC so I’m not sure if this line of enquiry will help much but what I would start with is opening the Inspection pane in your browser while you’re still in Files then opening Network tab and trying to open your document.

That way you should be able to see what is malformed.