Original firmware for HL-DT-ST BD-RE BH40N (FW GA05) after failed WH16NS60 flash

[Kokoro111]

Hi everyone,

I recently bought this drive from Lenovo:
Lenovo Part Lookup

According to the sticker, it is an HL-DT-ST BD-RE BH40N.
When I opened MakeMKV, it identified the chipset as MT1939.

Curious, I opened up the drive and found that it actually has a MT1959UWDN chipset.
So, I attempted to flash it with the WH16NS60 firmware. The flashing process completed successfully, but now the drive no longer reads Blu-rays.

I found someone in this thread who had the exact same issue:
Forum Thread, but I have firmware GA05 instead.

I also tried flashing the same firmware mentioned in that thread, but nothing changed – the drive still doesn’t work.

Does anyone have the original firmware for GA05? I have searched everywhere but couldn’t find anything.

I have attached some images that might help:

Normally, I can fix these things myself, but I’m really stuck this time. Thanks in advance for any help!