How is your torrc file ? Specially the lines : (commented by default with the # symbol) ControlPort 9053 CookieAuthentication 1 -->
sudo -u debian-tor ./run_nyx -i 9053
You can safely try this config, and reload Tor service with new config (on debian system)
systemctl reload tor
ps: may be I'm wrong... if someone have a better way to make it working ;)
This (or just "nyx") yields: Unable to connect to tor. Are you sure it's running?
OR (relay with control port, here example 9053) sudo -u debian-tor ./run_nyx -i 9053
This yields: Unable to connect to 127.0.1:9053: [Errno 111] Connection refused.
Errno being a Muppet previously unknown to me.