The only reliable tool for MediaTek MT6580 devices is SP Flash Tool (Smart Phone Flash Tool). Do not use QFIL (Qualcomm tools).
If your phone doesn’t power on at all (except for a red LED blink when connected to a PC), the preloader is likely corrupted. Flashing can revive it.
Gather the following tools and files:
Avoid random forum links. Recommended sources:
Filename example: Sanno_i7_Plus_MT6580_20231021_8.1.0.zip (Size: ~900 MB to 1.2 GB) sanno i7 plus flash file firmwae mt6580 update stock rom
Warning: Always download firmware from trusted sources. Corrupted or modified files can permanently damage your device.
You can find the firmware on:
File details:
Go to Settings → About Phone → Build Number. Write it down. Common builds for Sanno i7 Plus: The only reliable tool for MediaTek MT6580 devices
If your build number does not match any available download, do not flash blindly. Search for your exact variant.