This is the stock firmware for Jiayu G3T.
Download Link:Package of Jiayu G3T.
Flash Tool:Multi-road flash tool.
Then,following the steps in the picture below.
1.choose the two files in the flash tool package;
2.choose the firmware file in the firmware package;
5.Click “start all”
Now,turn off your phone and connect it with PC.Wait a few minutes until you see the screen shows in the picture above.