Are you trying to a dead device, or are you just looking to update to a newer version of Flyme OS?
If you encounter "PMT changed for the ROM," you may need to select "Format All + Download," though this can risk losing your IMEI (serial number) data. ROM Meizu M3 Note (M91 & L91) Official Repair F...
For standard updates or fixing minor software bugs. Firmware Upgrade: For unbricking or fixing bootloops. Initiate Flash: Click the Download button in the tool. Are you trying to a dead device, or
To perform an official repair, you will need the following files, typically bundled in specialized firmware packages: Firmware Upgrade: For unbricking or fixing bootloops
The official MediaTek utility for flashing deep-level firmware.
The requires specific "repair" or "unbrick" firmware when standard OTA updates fail or the device is stuck in a bootloop. Because these models use the MediaTek (MT6755) Helio P10 chipset, you must use the SP Flash Tool for a deep repair flash. Critical Firmware Information