A software restores through DFU Mode is an option. The device will be wiped and the software will be reset to factory settings. This will require a computer with iTunes installed in order to function. If you don't have access to a computer, you can have this troubleshooting step completed for you at an Apple shop.

1. Make sure you have the most recent iTunes version loaded on your computer.
2. iTunes should be open.
3. A nice lightning cable will connect your iPhone 7 to your PC.
   
4. Then, at the same moment, press and hold the Side and Volume Down buttons. Continue to hold them until the recovery mode screen appears.
5. When you see the Apple logo, be careful not to release the buttons. Hold on until the recovery is visible.
6. When you get the option to restore or update, choose Update. iTunes will try to reinstall iOS without erasing your data.
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