my MB 12 2015 was working until a few days ago and now it does not turn on. I assume that the battery is completely discharged and if I put it on charge the led I have on the usb-c cable turns on, so I assume that it is supplying current, but nothing happens. I tried to keep it open and connect the cable, but the small led next to the battery screw remains completely off. could it be the flat / usb connector or directly a logic board problem?