How to perform a hard reset when my Apple iPhone 5S is unresponsive
If the Apple iPhone 5S becomes unresponsive or doesn't perform as expected, you can perform a hard reset to return it to a factory default state.
Important: A hard reset will delete your data, apps and settings.
1. Ensure the iPhone is off.
2. Insert the USB cable, then hold the Home key while connecting the iPhone to iTunes.
3. On the computer, when prompted that iTunes has detected the iPhone in recovery mode, click OK.
4. Click Restore iPhone…
5. Click Restore and Update.
6. iTunes will begin to restore your iPhone.
7. Restore has completed successfully.
After restoring your Apple iPhone 5S, you may need to reactivate the SIM card using iTunes.