Find "Mobile networks"
Slide two fingers down the display starting from the top edge of your phone.
Press Shortcut to Settings.
Press Shortcut to Settings.
Press More....
Press Mobile networks.
Turn mobile data on or off
Press Data enabled to turn the function on or off.
If you turn on the function:
Press OK.
Press OK.
Return to the home screen
Press the home icon to return to the home screen.