“The blue light is on” - Do you mean the laser, or something else? If you do mean the laser, and it’s on but not very strong, it could be that you’re asking it to go too fast. Post a screen shot of the settings you used for the test and I can check that.
Another possibility is focus - have you focused the laser? There’s a small focus ring at the bottom of the laser. If you turn the beam on (at very low power) you can twist the lens to focus the beam to the smallest spot you can. Diode lasers are relatively low power, so they’re quite sensitive to good focus.
There’s a setting in LightBurn to help with this too: