Just a small tip, doublecheck all your user and group permissions after following that guide. I went through this before and the guide gave a bad instruction on the permissions for a folder that I ended up spending hours diagnosing. I still see at least one space where it tells you sonarr should be in the "sonarr" group and not the "media" group as previously instructed.
The guy they have that wrote these guides and answers all support questions for Sonarr and Radarr, he's an absolute asshole, bad at giving instructions, and often unhelpful. I'd say don't even bother with him.