Follow this step-by-step tutorial to learn how to reset network settings on iPhone, iPad or iPod.
Go to device settings.
Tap General.
Tap Reset.
Tap Reset Network Settings.
Enter the Passcode
If you have setup a passcode for your iOS device, you will be asked to enter it.
You’ll be asked to confirm Reset. Tap Reset.
This will reset your Network Settings, Wi-Fi networks and passwords, cellular settings, and VPN settings that you’ve used before.
It will take some time to restore network settings to the factory defaults. You will be notified when the process is completed.