Need help with Command line Switch (does not work)

Hi There,
i am using a curl command to switch something on via cmd:
command_on: curl -X POST "http://192.168.1.12:8080/rest/items/RollershutterEsszimmerlinks" -H "accept: */*" -H "Content-Type: text/plain" -d "ON"

and this is the part in configurationa.yaml, which is not working:

switch:
  - platform: command_line
    switches:
      switch1:
        command_on: '/usr/bin/curl -X POST "http://192.168.1.12:8080/rest/items/RollershutterEsszimmerlinks" -H "accept: */*" -H "Content-Type: text/plain" -d "ON"'
        command_off: '/usr/bin/curl -X POST "http://192.168.1.12:8080/rest/items/RollershutterEsszimmerlinks" -H "accept: */*" -H "Content-Type: text/plain" -d "OFF"'

What is wrong there?
Thanks cubert

Hi VDrainer,
Yes, its Hass.io on a raspberry.
I have read the guide, it could be the problem/solution but i just switch to mqtt.
I hoped the command line switch would be an easy solution for testing, but in the end mqtt is much better.
Thanks!