WireGuard Server on port 80

GL-MT3000 v4.2.2
How do I configure the WireGuard server to listen on port 80?

When I try to configure via the GUI I get an error message “-15,port:80 is in using” I’m not using port 80 for anything.

The Admin UI is using it.

If I remember correctly, someone asked how to change the ports the UI uses, so try searching the forum.