error = Conversion function not defined - is this key defined?

[7wells]

Hi Thomas!

I tried to change a value in the console of the broker ...
mosquitto_pub -t 'service/truma/set/vent_mode' -m 'Off'

... and received in MQTT Explorer this error message:
error = Conversion function not defined - is this key defined?

For a better understanding I looked in your program code for this message but could not find it. Maybe I looked not carefully enough or this message is not triggered by MQTT Explorer itself? Can you please guide me into the right direction where to further look for an explanation of this error? Thank you so much! 🙂