Error starting skill-esp8266

[JoergZ2]

I'll try to communicate with Sonoff-Switches with Tasmota-Firmware. My system: Raspberry Pi 4 with 4Giga, OS: Picroft fresh installation. On starting mycroft-cli-client, I get this errors:

    2020-03-10 08:27:10.669 | INFO     |   778 | mycroft.skills.settings:get_local_settings:78 | /opt/mycroft/skills/skill-esp8266/settings.json
    2020-03-10 08:27:10.816 | ERROR    |   778 | mycroft.skills.skill_loader:_create_skill_instance:249 | Skill initialization failed with KeyError('units')
    Traceback (most recent call last):
      File "/home/pi/mycroft-core/mycroft/skills/skill_loader.py", line 243, in _create_skill_instance
    self.instance.initialize()
      File "/opt/mycroft/skills/skill-esp8266/__init__.py", line 55, in initialize
    self.esp_units = self.settings["units"]
    KeyError: 'units'
    2020-03-10 08:27:10.825 | ERROR    |   778 | mycroft.skills.skill_loader:_communicate_load_status:286 | Skill skill-esp8266 failed to load

Normally I'm working with a local mqtt broker on ip 192.168.178.20. I don't work with http. Why is http used and can I deactivate it or replace with the mqtt topics and commands?