Hi guys! I think i solved the issue.
1) check if the bluetooth symbol in the BLE screen is ON. Probably it's off
2) change the battery. In my case was very low, and i think it can affect the bluetooth signal.
3) Reconnect to the hub.
Done
Same issue heres. Devices most of the time showing "not connected" and i can't see any temperature in the app. The device itself is OK and shows the correct temperature.
Also affects Home Assistant.
Any tips?