KNX 2 - How to retrieve physical address from an address group

Hi all,
I would like to retrieve the source physical address from an address group.
I just want to know which push button has switched on/off which light.
I don’t know how to identify the KNX transmitter of a KNX comand in openhab2.

I can see the physical address of the transmitter in the field “source” of a KNX frame (scanning the bus throught the monitoring of ETS5).

I try also to update an address group identifing the push button, but it is never updated and I cannot retreive any value.

Please let me know if I’m not clear.
Thanks and regards,
Louis