Having troubles flashing my benq dw1620a

i tried to update the firmware with b7p9 and b7m9 and it says that is not supported but i used the g7k9 and flash and it worked, what should i do? :confused:

G*** firmwares are for bulk drives, B*** are for retail. You have a bulk drive.

If you want to flash an OEM 1620 to retail, follow the instructions in this thread.