Activation and use of mqtt on Venus GX+Multiplus to use ESS mode 3: control ch/disch a battery

I am currently commissioning my installation consisting of a Multiplus 48/800/9 and a Venus GX connected via VE.Bus; I am trying to control the charging and discharging of a battery in ESS mode 3 using a Raspberry PI with Python.
I tried to use mqtt: i activate it on remote console:
see

when i check the availables services with python or with a mqtt analyser i only find that:

here is my python scripts to scan, but idon’t know how to proceed :slight_smile:
python script to scan mqtt.txt (1,4 Ko)

i thank you for your help,
Samuel Crégut