Rust's server list often takes 10 to 30 minutes to show a new server, and a server running Oxide is listed under the Modded tab. If you can connect with client.connect, the server works fine: it's just a listing delay.
Check that you're connecting with
client.connect IP:port(connection block).Look under the Modded tab if Oxide is enabled, Community otherwise.
Still missing after an hour: open a ticket, we'll check the query port (QUERY_PORT) on our end.
The server is only listed once it has finished loading: the console then shows "Server startup complete".