Px4 Firmware Upgrade Failed

Despite that I own multiple Pixhawks, one of the FCs wont upgrade it’s firmware using QGC (Px4 firmware) or MP (ArduPilot firmware). this specific Pixhawk wont start up properly like it used to (no main LED flashing nor beeping charms). although the device manager recognize the device as “Legacy FMU (COM4)”, QGC and MP wouldn’t sync and connect with the FC through it’s USB until many multiple attempts (I tried different USB ports on my computer and a brand new USB cable, no success).

Despite knowing that the firmware is installed within the board (not the SD card), I tried using a brand new micro SD card with no progress. The first following image is what I often get, but sometimes (If am lucky enough) the QGC prompt me to choose a firmware (Attempting to install Px4). Nonetheless, the second image is when the Upgrade fails [Error: Flash failed: Command failed: 0x11(PROTO_FAILED) at address 0x000fc000]

Any suggestions would be appreciated.