WiFi Dev board not being recognised

Hi

I recently got a WiFi dev board from Joom and it was delivered on time and well packaged. When it try to flash the firmware it will not be recognised by my laptop. So I tried it a few times more and even tried it on a further three laptops with no joy. I am doing as the update says and holding boot then plugging it in and holding for a further 3 -4 seconds but no joy.
Hopefully this is a simple fix, but Joom have said if after this post they will make sure I am satisfied which i think is good customer care. Thanks in advance

Hello! Can you please provide more information? Please tell us the OS of your computer, what commands you are using to flash the board, and, if possible, please record a full video of the procedure and post it here.