Black screen and phone not responding to button presses

You can change the topic title if you like

Do you think the phone is on, do you have an led light? I don’t know if adb can read an ‘off’ device.

By unauthorised you mean you can’t use your security pin?

Do you have a lot of data you don’t want to loose by a factory reset?

Do you have an SD card that is formatted as internal storage?

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