Why wont my computer turn off after rebooting

My computer installed or updated lenovo and it rebooted the computer and I accidentally unplugged it idk it that was the problem but now it when i unplug the charger it wont even light up or anything but when i plug it in the keyboard flashes and the lenovo startup screen turns on for maybe 2 or 3 seconds the goes black and the power button and esc button stay on thats it nothing else unless i hold the power button for 10 seconds then the screen cuts on for m2 second goes black the keyboard lights up then nothing again