First, let us try a quick test to ensure you phone can “see” the server.
Type this URL into your mobile browser, but replace 192.168.1.11 with your IP, 11111 with your port, and **** with your API key. Make sure to use “https” and not “http”
https://192.168.1.1:11111/time?key=****
If you get ah HTTPS warning, then the connection between devices is fine.
If you get a This site can’t be reached or similar error, then it’s a network issue.
Please try this and let me know the result.