Ensure you are holding the correct button (WPS or Reset) when plugging in, and that the battery is removed. Flash Failure:
Try a different USB port (use USB 2.0 instead of 3.0) or different USB cable. SIM Not Supported:
(or sometimes the Reset button) and immediately plug the USB cable into the PC while still holding the button. The M3y should connect as a Qualcomm HS-USB QDLoader 9008
Since specific firmware links change frequently, search for "Andromax M3y Unlock Firmware All Operator" on search engines for the latest working files.