I got the same issue, on two boards. Will probably try to burn the bootloader using usbasp, maybe they burned the wrong one back in china.
As expected flashing the micronucleus bootloader using USBasp solved the problem on both of the boards. I've used burn-o-mat as the arduino was not seeing my programmer.
Just download the firmware from github (I'...
Bootloader is poorly programmers it hand overs the overall hardware to user code,many people encounter error when uploading sketch second time.
Well i have solution though it may sound wears but it works for sure
"1.Disconnect board from USB ,
2.Hit upload button.,
3.Timout timer starts for 60 seconds.
4. Go ahead plug board to USB