Many CNC machines have a built-in safety that prevents them from traveling too far. The machine will stop and ask you to reset the machine
If you don't, it will set off an alarm and send an email or text message to your phone. You'll need to reset the machine so that it can start again
The problem is that this can trap people who are trying to fix something and they get stuck in the motion of resetting the machine.
cnc control setup for milling and turning by peter smid