Can't seem to access RustDesk web config page on my self-hosted Windows server. Any tips?

I've tried about 5 different guides to getting RustDesk server self-hosted on a Windows machine I use as a server and try as I might I can't get it working.

After installing, the server starts and runs fine, but in the display window I see

rustdesk local-ip: ""

like as if it hasn't found my machine's local IP...? And then when I connect to http://mylocalIP:21114 it goes nowhere. I see mention of different ports in the display window (21116, 21115 etc) but none of them work. And when I put that IP into my RustDesk client on another machine it won't connect.

So then I tried running RustDesk inside Docker for Windows but when I try to start it I get

Failed to run image. Error: (HTTP code 400) unexpected - No command specified

I have no idea what I'm doing wrong and feel it's probably silly to keep just blindly following Reddit guides without actually understanding what I'm doing.

Any advice would be welcomed!