I can't find my KAKU doorbell

I have a KAKU doorbell, which I would like to use to (also) send a message to my phone when it rings. However, I can’t seem to figure out how to add it to HA.

I have had this doorbell for years already and even used it in domoticz. Now I’m on HA for a while, using the same RFXcom receiver. When I look in the RFXcom integration, I see a total of 686 Devices and 2703 Entities. I have looked through other posts about this topic, and there I constantly see people saying:

Just add this code to your config.yaml and then a new device will appear when you press the doorbell button:

device: /dev/ttyUSB1
debug: false
automatic_add: true
fire_event: True

After adding the code and restarting HA, I pressed the doorbell multiple times, but I don’t see a new device. To be totally honest I don’t know where to look for it, so I just check the RFXcom list, but this remains the same count (686/2703), so nothing new is added there.

So then I figured, perhaps the doorbell is already in the list of binary sensors? There are hundreds of them in my entities list of this type (binary_sensor.ac_xxxxx). How am i supposed to find out which one it is?

So, long story short…I need help from a newby point of view. Until now, I’ve tried to copy some tricks from similar topics, but honestly I don’t really know what I’m doing exactly. I lack the proper coding knowledge. I would hugely appreciate someone helping me get a “dingdong” message on my phone eventually. But finding the doorbell is priority obviously.