An iPhone Unavailable or Security Lockout message appears after too many incorrect passcode attempts. If you cannot remember the passcode, the normal recovery path ultimately resets the iPhone and erases its current data.
- If you recently changed the passcode and the screen offers Forgot Passcode?, check whether the available passcode-reset option can use your previous passcode.
- If you cannot use that option, wait until Forgot Passcode? or the device-reset option appears on the lockout screen.
- Follow the prompts to start the iPhone reset and enter the Apple Account password when requested.
- If on-device reset is unavailable, connect the iPhone to a Mac or Windows PC, put it in recovery mode, and restore it with Finder or Apple Devices.
- Set up the erased iPhone and restore an available backup.
An on-device reset requires the conditions Apple specifies, including a network connection and, for the relevant workflow, Find My and the associated Apple Account. Repeatedly guessing the passcode only extends the lockout and does not bypass it.