Wifi connects for sometimes then disconnects and then never connects Their is a big issue of WiFi in my phone when i first bought it...

My phone is a Spice Stellar Mi-439, Android KITKAT v4.4.2, 1GHz Processor, 512RAM, 4GB Internal, currently 16GB Expandable.

The problem is that Wifi connects when i switch ON the Wifi and enter the WiFi network but disconnects after sometime of browsing and never connects again even by switch the WiFi ON-OFF-ON and not even by disabling Data Connection. Neither it disconnects when in Sleep or StandBy Mode, it disconnects during browsing or any time. Whereas other users on that WiFi network don't complain about any issue like that. I have no control over that WiFi Network.

It only works when i reboot the set but again disconnects after sometime.

I didn't got any solution from internet for it.

Any knowledge about this issue?
I have been testing one of my app on spice stellar phones. The problem seems to be with the phones as the Mac ID keeps changing (yes, that right). It starts with a specific Mac and then suddenly the Mac ID exposed to the network changes and the phone is dropped from the network. If I Forget the wifi connection and reconnect, the same behaviour is observed at random intervals.