What if even recovery mode doesn't work? Can you DFU for iOS 12?

• Use a Lightning to USB cord to connect your iPhone to your computer. If this is the first time you've connected your iPhone to this computer, you'll need to hit the Trust button in the Trust This Computer dialogue box. To complete the pairing, you'll need to enter your iPhone's passcode. Then, in a fast sequence, do the following:
• Press and hold the Volume Up button.
• Depress and release the Volume button.
• Hold the Side button for 10 seconds after pressing it.
• Press and hold the Volume down button for 5 seconds while still holding the side button.
• Hold the Volume down button for another 10 seconds after releasing the Side button.
• When you enter DFU mode successfully, your iPhone should display a blank screen. If the Apple logo appears, something went wrong, and you'll have to start over.
• The Finder should recognise that you've entered recovery mode if you're connected to a Mac. You should only see the Restore option instead of the Update iOS option, which is another sign that you've successfully entered DFU mode.

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