You could test with just one probe connected, and test all three. If a probe is faulty, it may block the transmission of the other 2 probes.
you can use the CLI with this tutorial.
the messages from the external temp probes will come from the src_channel = 8, 9, 10 and 11 of the device.
If you don’t see any messages from those src_channel numbers, your device may be defective and you have to change it to another. I have not seen that other users have caused so many problems with a smart implant