The flash file restores the device to the exact OS version it shipped with (typically Android Lollipop for this hardware generation). This ensures that the user experience remains consistent with what the hardware was optimized for. It includes the specific Lava UI skin, custom boot animations, and pre-installed system apps that define the brand's interface.
By following the information provided in this article, you should be able to successfully flash your Lava Iris 758 with a flash file and get your device running smoothly again.
on your PC so the computer can recognize the phone in flash mode. Required Files Lava Iris 758 Stock Firmware