Chosen Solution
I have a iPhone 6s plus that when I try to connect to wifi the button is grayed out I have reset the network setting and just all settings and I still cant get it to work I’m going to try and update it but i don’t think it will work any other things i can do
the wifi chip needs replaced
If the setting is greyed out, more than likely this is a hardware issue. You can certainly try resetting the device, but in all likelihood, it will not make a difference. Either the chip needs to be replaced, or something in the WiFi circuitry has sustained damage or has gone bad.
