Where do you get the message?
I get this message on the server side from the console
Service shouldn't have a console output. Are you running it manually?
I've stopping and starting the service from the shell:
sudo /etc/init.d/traccar stop
sudo /etc/init.d/traccar start
You should use scripts from /opt/traccar/bin
. If it still doesn't work, provide full output, not just a single line.
I get the message above and cannot connect any more. What is the issue? Disk space?