When it says disconnected, that's not wifi. It's telling you the AC is not connected to the RC. This can be due to flying too far from the controller, incorrect antenna positioning, antenna cable pulled loose or broken, the Phantom is off or not linked, etc. Are all the lights on the RC green when it says this? Is it happening while it's on the ground in front of you or when it's flying? I'm assuming on the ground because if in the air, it'll RTH. Give us some more info, please. Describe what you're doing when it says this. As we used to say in the photography forums, help us help you. Finally, is your device (phone, etc.) connected to the Phantom WIFI and not to a different WIFI? I have to manually set mine to tha Phantom every time I fly from my house because it automatically connects to my house WIFI.