Hello Harshitha, I am a bit confused about your question. You say that the PuTTY windows display the host name instead of the IP, which commonly would be regarded the preferred method since it is easier to recognize hosts by name rather than IP. I suspect your problem is that you don't have the target device name in the PuTTY sessions launched from PAM, but the local IP to which PAM makes the PuTTY client connect. If that is your problem, you should update the Client Application string in the TCP/UDP service you have defined in PAM. I use the following string:
"C:\Program Files (x86)\PuTTY\putty.exe" -ssh <user>@<Local IP> <First Port> -loghost <Device Name>
The "-loghost <Device Name>" argument results in the target device name being shown in the PuTTY Windows title: