You cannot change the nameservers of a domain registered with Cloudflare as indicated at the time of transfer. In most cases you shouldn’t need to as you can point the Cloudflare DNS at your hosting. If you must change nameservers, you will need to wait until the (ICANN mandated) 60 days have passed since the last transfer then transfer to another registrar.
I paused cloudflare and my site is now back up and running. As soon as the 60 days are up I am transferring it away. Nothing but issues with cloudflare. Very disappointed.
The host doesn’t respond to pings or connection attempts using either HTTP and HTTPS.
The MX record starts with _dc-mx as well, indicating that it contains a proxied hostname
That will cause email delivery issues. It is best to ensure that only hostnames are used in MX records.
As @epic.network has noted, the IP address of the host is not responding. The problem is with the host (or the IP address you have set), not Cloudflare.
As also noted, you need to make sure your DNS records for mail and smtp need to be set to “DNS only” as Cloudflare does not proxy mail connections.
For now, pause Cloudflare and check that everything works. Only when it does, re-enable Cloudflare.
As noted above, if Cloudflare is paused for your site (as it is currently), then all traffic goes directly to your host and does not pass through Cloudflare. You’ll need to push back at the host. They are fobbing you off.
With Cloudflare paused, the broadcasted DNS record should be what your host needs to check the site. Ask them if there are any issues with your DNS that would cause any issues with the site. They should at least be able to zero in on the one DNS record required to load your site.