What you should know about SP flash tool is that you shouldn’t interrupt a flash or read back process. If you do, the phone will go off and not come on at all. You might get the “USB device not recognized” error on further flashing attempts. If somehow, the process got interrupted and you now have a totally dead phone on your hands, don’t panic. All you need to do is connect the phone to a computer (via a USB cord) or power source and leave it to charge for some time. It could take up to two hours but once the phone is revived, your battery could read as low as 1% . just leave it to keep charging before powering it up.
Tips to speed things up
- Remove the battery > Connect the phone to a charger without battery inside > Slot in the battery while the phone is still connected to the charger.
- You could keep pressing the Volume up + Power button while charging
- You could remove and boost the battery using a desktop / external charger then resume internal charging.
- Uninstall then re-install MTK preloader vcom drivers using this guide @ How to Unbrick Mediatek phone