Hi! I understand you're having trouble with Mexican Train Dominoes Gold on your iPhone (iOS 16.7.12), where the new player cannot see the game that the host sets up. Let’s see if we can get that sorted out for you.

To clarify, is the new player trying to join via the in-app multiplayer feature? And do both the host and the new player have a stable internet connection? Sometimes connection issues can prevent the game lobby from appearing.

Here’s a step-by-step to troubleshoot:

1. Check Internet Connection:
Make sure both devices are on a stable Wi-Fi or cellular network with good signal.

2. Update the App:
Confirm that both the host and new player have the latest version of Mexican Train Dominoes Gold installed from the App Store. An outdated version can cause multiplayer visibility problems.

3. Restart the App:
Close the app completely on both devices and reopen it. This can refresh multiplayer sessions.

4. Create a New Game Lobby:
On the host device, create a new multiplayer game lobby and ensure it’s set to “public” or “visible” if such an option exists.

5. Check for Device Permissions:
Make sure the app has permissions to access the network. You can verify in iPhone Settings > Mexican Train Dominoes Gold > ensure Cellular Data and Wi-Fi access are enabled.

6. Try Private Lobby with Invitations:
If available, try hosting a private lobby and send the game invite directly to the new player through the app's invite system.

7. Network Configuration:
Sometimes network firewalls or VPNs on either device can block multiplayer communication. If either player is using a VPN, try disabling it temporarily.

If you have tried these steps already, please let me know which ones so I don’t repeat them, and I can guide you into more advanced settings or account checks.

Also, does the new player see other multiplayer games from other hosts, or is it only unable to see this specific host’s game lobby? This can help narrow down whether it’s a general visibility issue or specific to the host setup.

Let me know your experience with these steps, and we’ll get your game hosting and joining back to smooth play.