I also have the same problem… Thanks for trying…
Edit: I saw that the sense hat was faulty connected to pi4… I put it right and now I see the sensors. Also, the led matrix is turned off continuously and is fully controlled.
So Nikos in the end problem solved for you?
Just to let know everybody… my problem seems has to do with combination Pi3B and Raspbian 10. Probably some later updates of the Raspbian 10 make it impossible for Pi3B to work properly. Possibly on Pi4 with Raspbian 10 there is not such a problem.
A quick fix solution for me was…
I just installed the cayenne.mydevices , and Sens HAT on to an older Raspbian 9 version SSD on the same hardware and everything worked flawless. Of course I resisted to the temptation to
sudo apt-get upgrade
well not really a solution but for now will do…