1. Find "Carrier"
Slide two fingers downwards starting from the top the screen.
Press the settings icon.
Press More.
Press Mobile network.
Press Carrier and your phone will search for networks.
2. Select network
If you want to select a network automatically, press the indicator next to "Choose automatically" to turn on the function.
If you want to select a network manually, press the indicator next to "Choose automatically" to turn off the function.
Press OK.
Press the required network.
3. Return to the home screen
Press the Home key to return to the home screen.