My controller wifi connects with my iphone 8 but I'm getting a "No Internet Connection" message under Phantom__639bfb in my Wifi setting after it connects and the app shows "Connection to Phantom Failed". I'm able to fly the drone but the app is not communicating with the drone.
As said the no internet is normal, ignore it
usually the result of a bad binding, can also point to the camera as the issue.
follow the binding process below
turn off quad
turn on range extender
wait till the system light goes solid (may flash)
press reset button until system light goes out and STAYS out for at least 8 seconds
power on quad
wait till Phantom _xxx appears in wifi
open DJI VIsion App and go into settings > Binding
enter the MAC address (if not known scan QR code on quad)
WARNING IF THE WIFI MODULE HAS BEEN REPLACED THE QR CODE IS USELESS, USE A PROGRAM CALLED INSSIDER TO FIND THE SSID OF THE WIFI MODULE (HINT ITS AN UNNAMED SSID STARTING WITH 60 60)
press the blue tick and the tick again once the MAC address is entered
kill the app
turn off your phones wifi (not always needed but I do it)
wait 60 seconds
now try and connect to the wifi and open then app and check if the error has gone.
If the fault persists then it will be a camera issue, you will need to send the quad to someone who has a spare camera/ parts etc for fault diagnosis, im in the Uk and do repairs.