Why the laser only cut tow line in a row

[jkwilborn (Jack Wilborn)]

When the machine first connects, it will give a boot message identifying the firmware…

Can you copy/paste that?

Check this thread, it’s similar…

Sad new user: can't get past "error:20 Unsupported or invalid g-code command found in block"

You have setup your laser with the “iLaser” device type. Edit your device and switch this to “GRBL”. push “Devices” button in Laser window select your laser and then click “Edit” Change your device type and accept other settings Retest.