Seems a common issue. I read through all other posts, but cannot find a solution.
Plexserver is installed as Unraid docker.
I am only using in home network. I don’t plan to access remotely and have disabled this feature.
IOS and ATV devices work. Also, accessing the web app locally (my-IP:32400) work>
I am getting the error message only when trying to access via app.plex.tv.
Thanks for your help!