❔ How do I resolve the SocketException (10061)?

I keep getting System.Net.Sockets.SocketException (10061): A connection could not be made because the target computer actively denied it. (localhost:5003)

I just clone the dotnet podcast project from MSDN and trying to run it just as this guy. https://youtu.be/bnoCU5XGBh4?t=1160
https://github.com/microsoft/dotnet-podcasts

I've checked the computer listening on port 7522
but my 5003 can't be found I tried creating new rules on my firewall for both inbound and outbound traffic. (allowing all)

I've checked the 5003 with following commands
- netstat -a -n -o | find "5003" - returns nothing.
- netstat -aon can't find localhost:5003.

UPDATE:
The real culprit is this exception System.Net.Http.HttpRequestException

I suspect that the podcast.server is requesting from 5003. could it be that I need to run something else from the GitHub repository?