HINT Control Can't Find Any T-Mobile Gateway One Laptop Only

Any ideas why the HINT Control app (v 1.16.0) on my MacBook Air (one device only)" reports "no T-Mobile gateway found" on my network when I try to log in to my G5AR. My Mac Studio desktop, iPad and iPhone find it and HINT connects normally with the same saved login password, and local IP address. I have restarted the gateway, disconnected and re-connected Wi-Fi on the MacBook no luck.

No network changes, gateway IP and password good, or gateway changes ,but about three weeks ago I put all my devices on macOS 27 Public beta. I don't know if I have tried to use HINT on the MacBook Air since then, so it could be the culprit though a Mac desktop and 2 mobile devices on the same 27 Public Beta work normally.

Thanks for any "hints"

* G5AR, fw 1.00.03 * Built-in WiFi * 6GHz OFF * No Repeaters * Excellent signal at GW * Speeds up to 700/80 generally * This MacBook unwired 250/90