You can set your phone to select a network automatically or you can select a network manually. If you select a network manually, your phone will lose network connection when the selected network is out of reach.
Step 1 of 9
Slide two fingers downwards starting from the top of the screen.
Step 2 of 9
Press the settings icon.
Step 3 of 9
Press SIM card & mobile network.
Step 4 of 9
Press Mobile network.
Step 5 of 9
Press the indicator next to "Automatically select network" to turn off the function.
Step 6 of 9
Press OK and your phone will search for networks.
Step 7 of 9
Press the required network.
Step 8 of 9
Press the indicator next to "Automatically select network" to turn on the function.