Huawei P20 Pro
Android 8.1
Select help topic
1 Find "Mobile network"
Press Settings.
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Press Wireless & networks.
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Press Mobile network.
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2 Turn data roaming on or off
Press the indicator next to "Data 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
Press the Home key to return to the home screen.
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