The laser does not work, it follows the path but does not carve or cut

Turn off the laser and exit Lightburn. Without restarting Lightburn, turn the laser on. Do you hear the connection sound from your computer? If not, then unplug the USB cable from both ends and reconnect. You should hear the connection sound. If you still don’t hear the connection sound you may have a bad cable or other USB problem that I cannot help with.
If you do hear the connetion sound start Lightburn, go to the laser tab and click the dropdown next to devices and choose Com port.