Can't add Pluto TV

My docker container for Pluto TV is reachable and working but when I try to add Pluto as a source I keep getting the following error:

invalid source url: Get "http://SERVERNAME:8080/playlist.m3u": context deadline exceeded (Client.Timeout exceeded while awaiting headers)

I try by the domain name and the IP address but it makes no difference

So it looks like this?
Screenshot 2022-06-23 at 16-13-21 Pluto for Channels

Mine works. Here are the settings.
Just make sure the ip address and port are what you copied from the above webpage (Pluto docker) Playlist and EPG links

For XMLTV Guide Data, you may want to refresh more often. I have a cron job that does it every three hours, right after the docker container grabs new EPG listings every three hours.