PS C:\Users\me\projects\test> particle flash myargon tinker
attempting to flash firmware to your device myargon
Flash device OK: Update started
Flash success!
...same result when using a photon or electron - what type of device are you targeting? when you run the following in powershell: get-command particle - what do you get back?
in the meantime, it couldn't hurt to manually reset as updates can sometimes go oddly: