cwp - invaild hostname

I'm getting Your Hostname is: srv2.xryu.org and it resolves to IP: (ERROR: You don't have a valid hostname set!)

I have programmed the "DNS" Server and Cloudserver to use my other IPv4 37.49.224.243 and I had my VPS Host change it manually since it wouldn't change.
Everything in my "DNS Records" point to the new IP 37.49.224.243 of srv2.xryu.org

/etc/hosts (127.0.0.1) srv2.xryu.org & 37.49.224.243 srv2@xryu.org
/etc/hostname srv2.xryu.org
Zone: srv2.xryu.org.db Points to 37.49.224.243
/etc/resolv.conf - srv2.xryu.org 37.49.224.243

Everything points to the correct IP; YET I'm getting INVAILD Hostname. I don't get it. the rDNS Checks out. I also added srv2 on Cloudflare to point to 37.49.224.243 and mail to 37.49.224.243 yet it's not registering! I even restarted the Bind DNS Server several times after I rechecked the DNS Zones.

you need to add into your dns zone record for srv2.xryu.org.
You can try with editing the hostname and save it the same as it is, if that doesn't help then check manually your dns zone record.

Not that this needs to be done on your domains dns servers.

I already have the zone for it

srv2.xryu.org.db
and
xryu.org.db

I added the DNS Record for it already; but when I try to edit it; It says it has NO Owner. therefore i can't edit it, but this is the "Records" inside of it.
srv2.xryu.org. 86400 IN SOA ns1.centos-webpanel.com. info.centos-webpanel.com. (
srv2.xryu.org. NS ns1.centos-webpanel.com.
srv2.xryu.org. NS srv2.xryu.org.
srv2.xryu.org. A 37.49.224.243

I keep facing the issue rDNS/PTR = xryu.org FAILED than when I refresh the page, it says Success... (IT CANT) make up its mind if its success or failed. Its getting annoying.

What do I set my rDNS to? srv1.xryu.org or xryu.org ? My Hostname, or my Domain Name?

rDNS should be your hostname, you can also check if your hostname and rDNS match
http://www.senderbase.org/

kindly make sure that you had a dns record in your domain panel srv2.xryu.org @A to the ip of your server  this will work