The FBI has been unable to access Washington Post reporter Hannah Natanson’s iPhone so far because it’s protected by Lockdown Mode.
https://www.404media.co/fbi-couldnt-get-into-wapo-reporters-iphone-because-it-had-lockdown-mode-enabled/
FBI Couldn’t Get into WaPo Reporter’s iPhone Because It Had Lockdown Mode Enabled

Lockdown Mode is a sometimes overlooked feature of Apple devices that broadly make them harder to hack. A court record indicates the feature might be effective at stopping third parties unlocking someone's device. At least for now.

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