I think it was stated on the 17th that with the new update it was changing. Today someone posted about their server through GTX not working and one of the mods or whatever blacklisted their IPs. So I would assume that is why you’re key no longer works but a higher up would have to respond but I would assume that is the reason why.
The Key’s will work for Zap Hosting, VPS, Dedicated & Home hosted servers. Anything GSP related are being blacklisted/blocked which is why you will not see the server on the online list thus making people have to connect via IP Address.