Supported plugins
"xiaomi": All xiaomi bluetooth sensors, including
Flower Care plant sensor
Mijia Temperature and Humidity sensor
Mosquito Repellent

LYWSD03MMC Xiaomi Temp and Humidity Monitor ble 2 (https://de.aliexpress.com/item/4000373039226.html?spm=a2g0s.8937460.0.0.643c2e0e9wr1ld)

When you will use this sensor you must flash another Firmware from this site:

https://github.com/atc1441/ATC_MiThermometer

You can Flash the Firmware with the TelinkFlasher Tool from your Smartphone or from your PC (with active bluetooth module) from this site.

https://atc1441.github.io/TelinkFlasher.html

First you must download the new Firmware form here:

https://github.com/atc1441/ATC_MiThermometer/blob/master/ATC_Thermometer.bin

When your bluetooth module is off activate it.

Open the TeLinkFlasher Tool in your prefered Browser (Chrome works fine for me) and Push the connect button
Look in the connect screen for devices with Name LYWSD03MMC, mark it and push the couple Button.
You can see in the Log at the End on the Tool Page you are connected to the device.
Push the Do Activasion Button, when not you are not able to flash the new Firmware.
When Activasion is successful you can see in the Tool the Device known id, Mi Token and Mi Bind key.
Know you are able to flash Firmware.
Push the Button select Firmware, in the Dialogbox select ATC_Thermometer.bin.
Then you can flash Firmware with the start Flashing Button.
When it works you can see Status of the Flash Process.

After Flashing successful the sensor boot and you see Bootscreen with ATC and the last 6 digits from your sensor address (always 2 bytes displayed at the same time).
In TeLinkFlasher connect to the sensor Named with ATC_XXXXXX, where XXXXXX the last 6 Digits from your sensor address (see Boot Screen, you do not remember pull battery out an in and you will see the Boot screen again). Verify the connect in Log
Set the Advertising Type to Mi Like (you miss you have no correct data in ble adapter Objects !!), verify in the Log. 
Know you can use it in the ble Adapter