How to get sensor data from multiple nodes using sensor models ?

[sour11]

Hello guys ! i'm running : https://github.com/espressif/esp-idf/tr ... sor_models

I'm trying to get data from 2 or more server-nodes, but I got it just from the last node connected. . I has changed the uuid from the servers, but when I do this, the node can't connect. and i didn't know exactly how to use the group aspect .
Please can u tell me how to use the group strategy in the client and server codes .