Run the MTK USB VCOM driver installer on your PC and restart.
Ensure the device is fully powered off before connecting. Try a different USB port (preferably a USB 2.0 port on the back of the PC). Download K0706B Firmwar rar
Most K0706B devices require SP Flash Tool (Smart Phone Flash Tool). Run the MTK USB VCOM driver installer on your PC and restart
Power off your device completely. Hold the Volume Down (or Volume Up) button and connect it to the PC via USB. Download K0706B Firmwar rar