A system update appeared on my Note 2 when its battery was low so I decided to press updated later.Apparently my finger slipped and tapped the other one, causing my battery to eventually run down and brick my phone. Accoding to some guides, I tried to press thepower/volume up and then the volume down button, tried to swap my spare mpj battery and all other thing without the power. Nothing worked, is there any other solution i can try? I don’t want to send my phone back yet, thank you.
You hard bricked your phone. If you just let the battery go down, more and likely, you can fix this with a usb jig. You can build your own. But it is easier to just purchase one. You can buy one from ebay for $5. Just search up "usb jig note 2" on google and you should find several suppliers. If you have a corrupt partition or something of that nature then the above method won't work. You will need to go to someone who provides a jtag brick repair service.