Error while updating firmware on sim900a gsm module

i am having issue with updating firmware on my sim900a gsm module.
i got the right firmware, even i tried all sim900a firmwares still
it is giving me output as
error during load command
error during downlaod application in flash
check target settings

Are you sure, you selected the right firmware?
There are 32bit and 64 bit firmwares. You should select the right one based on your modules serial number. For more details mail to simcom support mahesh@sim.com . They should help you in selecting the right firmware.

can u write the name of the firmware version you have

I have tried all types of sim900A firmwares 32 bits as well as 64 bits