Today, CPPS.one announced their sudden closure, with the developer abandoning the project.
A notice was left within the CPPS.one discord server, and the website further explaining the situation, and confirming the closure:
CPPS.one first joined us in 2015, then made its short-lived return earlier last month.
If you are wanting to claim CPPS.one’s game server & media assets, you are instructed to contact Ben#2732 via discord.
As recommended, you can join CPPS.pw here.