Right now, that site isn’t proxied by Cloudflare, so it’s a hosting issue.
Your best bet is to use the “Pause Cloudflare on Site” option from the lower right corner of the Overview tab in dash.cloudflare.com, then wait five minutes for it to take effect. Then make sure those URLs work correctly with HTTPS.
If you can’t get it to work with Cloudflare paused, then contact your host. They should be able track down the problem.