iphone can't connect WiFi solution without WiFi

method One: after we click on "Set-Wireless LAN" in the Apple device, we click on the small exclamation point next to the WiFi network and go to the WiFi management interface. We click on "Ignore this network" and then reconnect to the WiFi network, so we can see if the WiFi network is connected successfully.

Method Two: "Restore network Settings" click "Settings-General-Restore-Restore network Settings" on the Apple phone, as shown below.

Method Three: The ultimate big trick--directly restart the phone.

If none of the above three strokes can be solved, there are two possibilities. One possibility is that the wireless router's version is too low, and the iphone's WiFi chip is more high-end and poorly supported; another possibility is that the iphone's hardware is problematic and needs to be overhauled.