Samsung Galaxy A50
Android 9.0
Select help topic
1 Find "Network operators"
Slide two fingers downwards starting from the top of the screen.
Press the settings icon.
Press Connections.
Press Mobile networks.
Press Network operators.
2 Select network manually
Press Select manually and your phone will search for networks.
Press the required network.
3 Select network automatically
Press Select automatically.
4 Return to the home screen
Press the Home key to return to the home screen.