15 Troubleshooting ................
Before contacting the service centre, you are advised to follow the instructions below:
•You are advised to fully charge ( 
) the battery for optimal operation.
•Avoid storing large amounts of data in your phone as this may affect its performance.
•Use Factory data reset and the upgrade tool to perform phone formatting or software upgrading (to reset factory data, hold down the power key and the Volume up key at the same time). ALL User phone data: contacts, photos, messages and files, downloaded applications will be lost permanently. It is strongly advised to fully backup the phone data and profile via ONE TOUCH Manager before doing formatting and upgrading.
and carry out the following checks:
My phone is frozen or cannot be switched on
•Check the battery power level, charge for at least 20 minutes.
•Press and hold Power key for more than 7 seconds to try to restart.
•If it still does not work, please reset the phone using the Power key and the Volume up key.
My phone has not responded for several minutes
•Restart your phone by pressing and holding the Power key.
My phone turns off by itself
•Check that your screen is locked when you are not using your phone, and make sure the Power key is not
•Check the battery charge level.
My phone cannot charge properly
•Make sure that your battery is not completely discharged; if the battery power is empty for a long time, it may take around 20 minutes to display the battery charger indicator on the screen.
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•Make sure charging is carried out under normal conditions (0°C to +40°C).
•When abroad, check that the voltage input is compatible.
My phone cannot connect to a network or “No service” is displayed
•Try connecting in another location.
•Verify the network coverage with your operator.
•Check with your operator that your SIM card is valid.
•Try selecting the available network(s) manually (see “11.1.8 Mobile networks”)
•Try connecting at a later time if the network is overloaded.
My phone cannot connect to the Internet
•Check that the IMEI number (press *#06#) is the same as the one printed on your warranty card or box.
•Make sure that the internet access service of your SIM card is available.
•Check your phone's Internet connecting settings.
•Make sure you are in a place with network coverage.
•Try connecting at a later time or another location.
Invalid SIM card
•Make sure the SIM card has been correctly inserted (see “Inserting or removing the SIM card”).
•Make sure the chip on your SIM card is not damaged or scratched.
•Make sure the service of your SIM card is available.
Unable to make outgoing calls
•Make sure you have dialed a valid number and have touched 
.
•For international calls, check the country and area codes.
•Make sure your phone is connected to a network, and the network is not overloaded or unavailable.
•Check your subscription status with your operator (credit, SIM card valid, etc.).
•Make sure you have not barred outgoing calls.
•Make sure that your phone is not in flight mode.
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