I don’t have a lot of new stuff to add here that wasn’t already offered by the amazing advice above, but I do want to add some support for a couple key points even though it’s already been mentioned:
No, sometimes camera flashing doesn’t work right with exFAT for some reason. Switch it back to FAT32 with cards 32gb in size or less. That has a higher success rate. It’s not that exfat never works, but flashing fails a lot more often with large cards in exfat.
As @WildBill said, some people have reported that flashing continually failed until they tried an 8 GB partition. I’ve never had that problem, but I know some people who I trust have said that definitely made a difference for them in some cases.
I have flashed dozens and dozens of cameras. Sometimes it’s finicky. Let me share a couple key points when a camera is not immediately taking the flash.
Sometimes, what you need to do, is after you initiate the flash. Wait a long period of time. Just leave it plugged in and act like it takes something like 30 to 60 minutes for the flash to be effective. Then go back, and try to go through setup again a Long time later. If it doesn’t work, factory reset the camera by holding down the reset button for 10 seconds and then go through setup again. There have been times where the firmware flash seems to have failed, but then I wait a long time and then it suddenly worked. Other times, the firmware flash seems to have failed, but I restarted the camera and the setup process worked after a restart. A restart. Then there were other times where the firmware flash seemed to have failed, but doing a factory reset, worked and brought the camera back. So sometimes, it seems like the firmware flash failed but it didn’t necessarily fail. But if you keep trying to do the firmware flash again, you may keep having it not work because maybe it is working every time. But it needs you to eat their wait a while or reset it or factory reset it first. It’s dumb, but I promise that has for sure happened to me sometimes, though it is very rare.
There was one device that I thought for sure must have been bricked, I tried flashing it dozens of times, and it always failed, and I thought I was insane because I kept trying the same thing over and over again but kept getting the same result, but then once after dozens of attempts it randomly worked, SO thankfully I can continue to pretend I’m not insane yet. I’m not saying it’s worth it to try flashing the same device that many times, I’m just saying it worked for me one time 