1. Find "Mobile network"
Slide two fingers downwards starting from the top of the screen.
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Press the settings icon.
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Press Network & Internet.
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Press Mobile network.
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2. Turn data roaming on or off
Press the required SIM.
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Press the indicator next to "Roaming" to turn the function on or off.
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If you turn on the function, press OK.
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3. Return to the home screen
Slide your finger upwards starting from the bottom of the screen to return to the home screen.
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