2022-02-02 08:41:20.684 [WARN ] [ab.binding.mqtt.generic.ChannelState] - Command ‘8B8FE1’ not supported by type ‘ColorValue’: 8B8FE1 is not a valid string syntax
This is probably your openHAB Thing Channel complaining that your real device is publishing 8B8FE1 to the MQTT topic that this Thing Channel is subscribed to. But a ColorValue type Thing Channel cannot process 8B8FE1, so ignores it and prints a warning in the log.
Looks like your real device is trying to publish a colour in hex, but the ColorValue Channel can only accept hsb or RGB or xyY.