I have encountered the same but using fhem…
So when “searching” for new sensors in deCONZ/Phoscon it shows “green” and “ready” but the sensor does not show up in the “App”.
But then surprisingly I could find the sensor in fhem.
fhem ist connected using the REST API as far as I know…
I was in contact with DE support and the guy told me to open up a task here but then I found this and thought at least place a message here
Actually I do not have access to the sensor and deCONZ setup (running in a garage at a friends house) and the actual status is “ok” for me so…
This is the information I got from an test integration with zigbee2mqtt:
Temperature & humidity sensor with display
Not sure if that helps…
…but it did not hurt me posting
P.S.: thanks to the support of DE!!