If your Sony Xperia C4 phone has slowed down considerably or isn't working properly, it may be necessary to proceed to a reset.
Before you try the factory reset or hard reset on your device,First make sure that you have backup all your important files.
Restoring the default settings or factory reset your device will delete all your existing files and will go back to its initial state.
Factory Reset:
1.First On your Home screen, tap Apps.
2. Go to Settings, and select Backup then reset.
3. Tap on Factory data reset.
4.Then Reset phone.
5.Confirm by tapping Erase everything.
NB:
You just need to wait while your phone deleting your files and restoring your settings to default.
Hard Reset:
1.Turn OFF your phone. Press and hold the Power button, Volume Up and Volume Down buttons all together.
2.There should a menu will appear on your phone. (If it does not work, try to Press and Hold the Power button)
3.Press the Volume down button to navigate to the Recovery option.
Press the Volume Up to select (if that doesn't work, use the Power button to select).
4.An Android logo will appear.
Press the Volume Down and Volume Up button together and a recovery menu should appear.
Use the Volume buttons to move to the Wipe data/Factory reset option and then press Power to select.
5.Use the Volume Down key to choose Yes and press the Power button again to select.
