Download latest Android KitKat 4.4 stock firmware for Uhappy UP320 smartphone from here or from here.
Model： Uhappy UP320 smartphone
Image file size: 482 MB
Platform: Mediatek MT6752
Caution: Please do not update firmware unless you know what you are doing, you really want it or it is absolutely necessary. Firmware updates may occasionally have bad results, like bricking your device, temporarily or permanently. The firmware update process is done entirely at your own risk. Before attempting to update the firmware, back up your data.