Nodemcu POST Response “-1”

Question

Nodemcu device is returning HTTP response -1 for a POST request on django rest api.

I tried the below http request to Postman, and it works perfectly fine.

http://localhost:8000/api/datalogs/?plant=http://localhost:8000/api/plants/1/&light=23&temperature=24&humidity=75&soil=Dry&moisture=787&remarks=/

This is my arduino post request:

if(WiFi.status() == WL_CONNECTED) {
    HTTPClient http;

    http.begin(host_url);

    http.addHeader("Content-Type", "application/x-www-form-urlencoded"); 
    httpCode = http.POST(postData);

    payload = http.getString();
    http.end();
}

The expected result is 200, but I get -1. Can someone please explain?