Samsung Galaxy Tab A
Find "Mobile networks"
Slide your finger down the display starting from the top edge of your tablet.
Press the settings icon.
Press the settings icon.
Press Mobile networks.
Turn data roaming on or off
Press Data roaming 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 key to return to the home screen.