support.apple.com/iphone/restore

Hello,

You can get your iPhone into recovery mode and plug in the iPhone to the computer. You should see a pop up on the computer asking to “update” or “restore”.

• You can try “update”, this way it will only update and won’t delete your data.
• If that does not work, choose “restore”, this will delete all data on the iPhone and you will need a previous backup to get your data back.

You can follow the instructions here: https://support.apple.com/HT201412

go to https://support.apple.com/iphone/restore and follow the instructions there...

Hi,

Unfortunately you can’t restore the iPhone without a computer because there is an issue with the iPhone and can’t erase itself.

• You can try holding the power and home button together for a few seconds to see if you can exit the support.apple.com/iphone/restore screen.

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