Add RD Session Host to Existing RD Session Collection

Hi everyone,

I use Windows Server 2012 environment, I have installed one server which has RD Session Host, RD Session Broker. then I decided to add one more server into the this my collection. I installed same roles to new server but when I click to Add RD Session Host Servers I cannot see new server,how can I add second , third servers to existing my collection? thanks in advance.