When the device is in Preloader mode (e.g., holding volume buttons while connecting USB), the SoC enumerates as a MediaTek USB port (VID 0x0E8D). The host sends a sequence of :

Newer MT6789 devices might have patched the vulnerabilities that older versions of mtkclient relied on.

Some devices have strictly locked bootloaders that cannot be unlocked via official fastboot commands. Bypassing the BROM protection allows developers to force-modify the bootloader status flags. The Mechanics: How the Bypass Works

When a MediaTek device powers on, the very first code to execute is embedded directly into the silicon. This is the BootROM (BROM). The BROM is read-only memory; it cannot be modified or updated. Its primary job is to initialize minimal hardware and establish a secure environment to load the secondary bootloader (Preloader). The Authentication Lock (DA Auth)

Use the command to initiate the bypass: python mtk da --loader DA_BR.bin (Make sure to use a valid DA_BR.bin designed for MT6789/V6) .