The firmware package available is an update package, to be flashed from your phone’s SDCard.
The download below is ZTE U960E official stock ROM. If you have any problems using the link below, post in comments section and we’ll try to provide you an alternate download link.
ZTE U960E ROM – Download
How to flash
Follow the flashing instructions available via this link https://www.leakite.com/2016/09/how-to-flash-zte-stock-rom-firmware-via.html