GRBL default Settings
Some time, the GRBL board can be connected, but can't move the motor, maybe the settings goes wrong.
Try reset the grbl settings using Engraver Master.
If you are using Candle / Bachin Draw software, please enter a command to do this.
$RST=*
For more information, see: https://github.com/gnea/grbl/wiki/Grbl-v1.1-Configuration