my public ip not showing?

hey everyone, super new to this whole saas thing, just launched my first web tool. it's a pretty simple 'what is my ip address' tool, basically an ip address lookup, but i'm having a weird issue.

sometimes, it just doesn't display the correct public ip. like, it shows a local one instead, or sometimes nothing at all. i'm using a common apii for the ip lookup service, but maybe i'm missing something in my config or how i'm calling it? i'll include a fake 'console output' snippet below to show what i mean.

// successful call output
{
  "ip": "203.0.113.45",
  "country": "US",
  "isp": "ExampleISP"
}

// problematic local ip output
{
  "ip": "192.168.1.100",
  "type": "private",
  "error": "Local IP detected"
}

// another problematic one (empty or malformed)
{}

anyone faced this before or have tips for reliablly getting the public ip?