This feature allows you to reset the device's network settings to the original default.
How to reset network settings to default on Sony Xperia L1 is as follows:
Step 1: Go to Settings and select Additional settings.
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Step 2: Select the option to reset network settings.
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Step 3: Choose the reset option.
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With these steps, you have completed the setup. Wishing you success.
Explore more guides on Sony Xperia L1 here