The laser won't fire or the machine won't start?
Does/can you move the cutting head manually?
Sorry, not familiar with them but with most machines, do some basic troubleshooting like:
0. The machine of course has power (sorry for asking but you'd be amazed)!
1. Any error messages on screen or control panels, error indicators, check them against the operator/technical manual
2. Any fault indicators on electronics modules (see item 1)
3. Check fuses, circuit breakers and replace any blown fuses and/or reset breakers
4. The machine of course was working, anything changed - find out and undo if that could be a cause
If it's CO2 based, has it got gas?