The ZTE T230 stock ROM contained in this post is flashed via Upgrade tool as the device is based on Spreadtrum CPU.
After downloading the firmware from below provided link, follow flashing instructions at the end of this post if you don’t know how to use Research Download Upgrade Tool, or if you only need to download the tool.
ZTE Smart 9 (T230) – Download
!Important! – Password: htetrkar
How to flash firmware package
For Upgrade Tool download link and flashing instructions, follow this link https://www.leakite.com/2015/11/how-to-flash-stock-rom-firmware-on-any.html