…maybe try a factory reset. hold com button when you start the unit. follow on screen instructions.
…if you press and hold the info button when it’s attached to the usb cable it should show you the current loading state near the on/off switch. via the LED’s.

Thanks for the aswer, i have done both of these steps already, it doesnt change the situation. It could be a problem of the machine itself?
…hhmm yeah of course. is it a new device? then send it back if not you can try to reinstall the actual OS.
I was having all kinds of weirdness with mine not turning on and a fresh OS install did the trick.
Attacking with a usb could be a little rough. Try attaching it Also maybe make sure that the charging function while turned on and plugged in is on.
Use the cable supplied by TE and hook it up to a computer that is turned on. Then in the options screen, check that USB charging is enabled. Then turn the OP1 off and leave it to charge for a few hours. If it still won’t work afterwards, send it back to TE.
Use the cable supplied by TE and hook it up to a computer that is turned on. Then in the options screen, check that USB charging is enabled. Then turn it off and leave it to charge for a few hours. If it still won't work afterwards, send it back to TE.
I would even say a whole night : when the battery is totally empty, it takes some time before it can get to full charge again.