M66FA Firmware Upgrade Error

Dear,
Again, thank you for your great support!
I still have issue while trying to upgrade the firmware(M66FAR02A09B) of M66FA mobules using QFlash 5.5. I’m unfortunately getting the error message “FAIL, ERR_2006_S_BROM_CMD_STARTCMD_TIMEOUT”. Let me explains how I proceed:
-Have the dev. board M10EVB and a new M66FA module completely external to M10EVB and connected in isolated manner, meaning
ME10EVB M66FB
MAIN USART is connected tp PC
VBAT ---------------------------------------------> VBAT, pin 43
GND ----------------------------------------------> GND, pin 36
|--------------------------------------------------PWRKEY (connected GND)
TXD------------------------------------------------>RXD, pin 18
RXD ------------------------------------------------>TXD, pin 17

See more detailled information in the following attached picture

I want to upgrade the Firmware of the M66 before the assembly process of the final design. And once the GSM Modules M66 are upgraded then start with the assembly.

Could you please advice on how to upgrade the firmware of an isolated M66?

Regards,
Baron T.

Dear,

could you please help with this issue. As described above, I’m not able to upgrade the firmware of the GSM Module M66.

Could you please advice?

Kind regards,
Baron T.