U2415, OSD has no power cannot turn on

I've had two U2415s for 5 years ago running side by side. Today the left monitor OSD doesn't work, no power to the monitor at all it seems. The right one works fine. 

I have unplugged it and touched the power for 15 seconds, there is no "button" just the touch OSD and plugged it back in again but nothing. The light will not even light up any more. I've tried 3 separate main plugs and nothing works.

Is it dead?