We have recently pointed our A records for qjumpers.com and www to a new website server IP address as we have developed a new site for them. The site will load if the proxy (orange cloud) is switched off but when it is switched on, it renders the old website for some reason.
(3) Wait 60 seconds to apply, and then try browsing your website in incognito mode with your local cache disabled. You should see the new website even when the ‘orange cloud’ proxy is enabled.
Who provided the old website? There are cases where you need to get the old provider to delete the domain if they were using certain Cloudflare configurations.
I have seen funny DNS related caching issues after changing nameservers, maybe due to TTLs. I had a client website with a similar issue, but it would show the correct website on mobile data only, no matter how many DNS flushes. The ISP DNS server was using the wrong nameservers. It took nearly a week to resolve itself (new customers hit the new website immediately).
Have you tried a different device and a different internet connection?
There is definitely something strange going on with that domain.
If I look at the CT logs I see lots of Cloudflare issued certificates for that domain, and several different Common Names. My best guess is that your client had a CNAME setup for www.qjumpers.com, and that is still active, and taking precedence over the normal domain.
I’ll escalate for somebody with more information to take a look.