Digits web interface not running after reboot

I just set up an instance. The web interface was accessible after the first boot, but not after rebooting.

Nothing is listening on port 5000 anymore:

ubuntu@ip-172-31-40-32:~$ netstat -ln
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State
tcp        0      0    *               LISTEN
tcp6       0      0 :::22                   :::*                    LISTEN
udp        0      0    *