Certain Iphones not connecting to LAN after first time connecting..

I have a Lan Setup, having hosting an instance server on my computer. One of the iPhone connect through UNET, after disconnection, when trying to connect again, the server instance doesn't receive any type of message of that connection, and the IPhone won't able to connect to the instance ever again.

I have windows firewall turned off from my computer.
I was able to ping the phone from my computer.