I have imx8mmevk. In the beginning, it is working fine with custom image.While I clean image & rebuild it, for the first time it starts. But when I flash the same image again, it gets auto-boot.
The most likely cause of the issue you describe is that the boot media becomes damaged for some reason when you flash it for the second time. Please make sure to clearly erase the boot media before re-flashing it.
Retrieving data ...