Errors that often appear in the log - platform: command_line - On-Off Plug Wi-Fi

Hi,
I have 3 Chacon On-Off plugs Wi-Fi with the firmware hfeasy (https://github.com/ljalves/hfeasy),
I use the commands below to control them,

switch:
  - platform: command_line
    scan_interval: 30
    switches:
      plug1:
        command_on: "curl -X GET http://192.168.1.8/state?sw=1"
        command_off: "curl -X GET http://192.168.1.8/state?sw=0"
        command_state: "curl -X GET http://192.168.1.8/state"
        value_template: '{{ value_json.relay_status == "1" }}'

  - platform: command_line
    scan_interval: 30
    switches:
      plug2:
        command_on: "curl -X GET http://192.168.1.9/state?sw=1"
        command_off: "curl -X GET http://192.168.1.9/state?sw=0"
        command_state: "curl -X GET http://192.168.1.9/state"
        value_template: '{{ value_json.relay_status == "1" }}'

  - platform: command_line
    scan_interval: 30
    switches:
      plug3:
        command_on: "curl -X GET http://192.168.1.10/state?sw=1"
        command_off: "curl -X GET http://192.168.1.10/state?sw=0"
        command_state: "curl -X GET http://192.168.1.10/state"
        value_template: '{{ value_json.relay_status == "1" }}'

The problem is that I often find the same errors in the log,
And sometimes moments of inactivity of several seconds in the history while the plug is working,

Command failed: curl -X GET http://192.168.1.***/state
*** = 8, 9 or 10

Error parsing value: ‘value_json’ is undefined (value: None, template: {{ value_json.relay_status == “1” }})

Update of switch.plug*** is taking over 10 seconds
*** = 1,2 or 3

Could there be a way to correct them please?