arduinclient won't post json

Using Arduino Networking, Protocols, and Devices
#1

we tried to send json build with arduino json to a php page, the page response the sended post data.
after running below code the post is empty.
can someone explain what we do wrong.

 String postData = "{\"naam\":\"ik\"}";
         String dataStr = postData;

          apiconnectie.beginRequest();
          apiconnectie.post(path);
          apiconnectie.print("Content-Length: ");
          apiconnectie.println(postData.length());
          apiconnectie.println();
          apiconnectie.println(postData);

     
          apiconnectie.beginBody();
          apiconnectie.print(dataStr);
          apiconnectie.endRequest();

          statusCode = apiconnectie.responseStatusCode();
          response = apiconnectie.responseBody();

          Serial.println("Status code: ");
          Serial.println(statusCode);
          Serial.println("Response: ");
          Serial.println(response);

thanks for your time

#2