My Garry's Mod Server Won't Show Up in The Internet Tab

I made a gmod server for both TTT and regular Sandbox. The TTT one is fine (now I just need friends to play it with), but the Sandbox one refuses to show up on the internet tab. I am the only one who can see it or join it. I’ve redownloaded all the server files once already and it didn’t help, and I’ve restarted it a million times, so if anyone has a solution, I’d love to hear it (even if it’s dumb).