Sending a request through Cloudflare with your domain returns the following response
HTTP/1.1 301 Moved Permanently
Date: Tue, 04 Sep 2018 16:55:25 GMT
Set-Cookie: <-------->; expires=Wed, 04-Sep-19 16:55:25 GMT; path=/; domain=.molearchitects.co.uk; HttpOnly
Expect-CT: max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"
<head><title>301 Moved Permanently</title><script src="/cdn-cgi/apps/head/eanNMiNcihKxXJ49YbtQwinTous.js"></script></head>
<center><h1>301 Moved Permanently</h1></center>
Considering the redirect HTML shows the same nginx version as your server I would assume it does come from your server. However a request directly to your server does return a proper 200. Are you sure your Cloudflare configuration does point to the same server? So basically, when you disabled Cloudflare have you just switched to or have you changed something else DNS-wise as well?