Jailbreak ATV2 with firmware 8.4.2

I recently update by mistake the firmware to 8.4.2 and afer that I decided to jailbrak my ATV 2

I tride several time but at the end the follow message appear:

“error entering dfu mode this device is not supported by season pass”

Then connecting the atv2 to PC with only usb cable, no light is on, I am forced to use power cord

What’s the problem?

Thanks and regards