esp8266 12E wifi station mode

[dprem06]

Esp8266 12 E Doit chip wifi is not connected.

My Code: ( I wrote in Arduino IDE)
My board Selection is -> GenericEsp8266

#include <ESP8266WiFi.h>
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
Serial.println(" i am started");

WiFi.begin("prem@mpbros","prem1234");
while (WiFi.status() != WL_CONNECTED)
{
delay(1000);
Serial.print(".");
}

     if (WiFi.status() == WL_CONNECTED)

{
Serial.println("WiFi connected");
Serial.println("IP address:");
Serial.println(WiFi.localIP());

Serial.println("Mac Id:");
Serial.println(WiFi.macAddress());
}
}

void loop() {
// put your main code here, to run repeatedly:

}

Its not connected its .........................(untill 1 hour no connectivity) please help me how to do this.