Posting data from esp8266 to a webapi - asp.net-web-api

Question

I want to send data from my esp8266 to a webapi but it fails.
I tried this code to send my data like sensor status but it fails and returns error 400. I searched a lot about this problem and I tried so many things but it didn't work.
#include <Arduino.h>
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include <ESP8266HTTPClient.h>
const char *ssid = "VRU";
const char *password = "";
const char *host = "192.168.174.71";
WiFiClient wifiClient;
void setup() {
delay(1000);
Serial.begin(115200);
WiFi.mode(WIFI_OFF);
delay(1000);
WiFi.mode(WIFI_STA);
WiFi.begin(ssid, password);
Serial.println("");
Serial.print("Connecting");
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.print("Connected to ");
Serial.println(ssid);
Serial.print("IP address: ");
Serial.println(WiFi.localIP());
}
void loop() {
HTTPClient http;
http.begin(wifiClient,"http://192.168.174.71:100/api/StatusReport/AddStatus");
http.addHeader("Content-Type", "application/json");
int httpCode = http.POST("{\"status\":\"1\"}");
String payload = http.getString();
Serial.println(httpCode);
Serial.println(payload);
http.end();
delay(5000);
}
Here is my code. It connects to the wifi without any problem and when it wants to post the data it returns an error.
400
{"type":"https://tools.ietf.org/html/rfc7231#section-6.5.1","title":"One or more validation errors occurred.","status":400,"traceId":"00-862f434a8be85865c871ea45b89544d1-cea4232cafaa5cc1-00","errors":{"status":["The status field is required."]}}
And it's the error.
The api receives the data when I do it by myself but the esp can't send the data.
What should I do to prevent this error from happening. Is it from the api that can't receive data or from the esp?