If after trying every other fix described here, you still have issues with your Android device, wiping the cache and data partitions and returning it to its factory presets will restore the device's software to like-new condition. But consider this your last resort: The process of wiping data and restoring factory presets is akin to the process of reformatting your PC's hard drive and installing a clean copy of Windows. You'll lose every bit of personal data stored on the device's internal memory and will have to reinstall all of your apps.
If that outcome is acceptable to you, enter recovery mode on your device and choose the options to wipe cache and wipe data. When you reboot your device, it will behave as though you were powering it up for the first time.
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