Download Oppo Joy 3 A11w Stock ROM
Install MTK Driver
1- Download the package & Extract Oppo Joy 3 A11w Flash tool.
2- Out of the icon appearing, Double click on Flash_tool.exe
3- it will launch the tool on your PC, Click on Scatter-Loading appearing on the Right side of the tool.
4- Now, assign the firmware which will be in form "Android_scatter.txt".
5- Select Firmware Upgrade in drop down.
6- Click on Download to start flashing.
7- Switch off your Mobile and Connect it to PC by pressing Volume down or Volume up key.
8- It will lead you to Successful Flashing