Read the statement by Michael Teeuw here.
UNSOLVED Auto boot suddenly not working
I built my first MM just after the new year. Was working great (love this site!) and would always automatically startup upon rebooting the Pi, using mm.sh as described in the tutorials. Then last week (don’t remember which day exactly, I’m just getting to it now), it stopped automatically starting when Pi reboots. I can manually start using npm start, but it won’t do so automatically. If it helps, whenever I try to execute pm2 commands, nothing happens, I just get the following:
[pm2] spawning pm2 daemon with pm2_home=/home/pi/.pm2