Sending request to bitcoin fullnode using libcurl

I am trying to send a request to my bitcoin full node. If I type this in my command line:

curl --user user:pw --data-binary '{"jsonrpc": "1.0", "id": "curltest", "method": "getblockcount", "params": []}' -H 'content-type: text/plain;' http://127.0.0.1:8332/

I get the answer I want:

{"result":709554,"error":null,"id":"curltest"}

However if I try to replicate the exact same command in C++ using libcurl I always get an empty answer:

#include <iostream>
#include <string>
#include <curl/curl.h> 
#include <stdlib.h>


struct MemoryStruct {
  std::string cont = "";
};

static size_t WriteMemoryCallback(void *contents, size_t size, size_t nmemb, void *userp)
{
   struct MemoryStruct *mem = (struct MemoryStruct *)userp;
   mem->cont += (char *) contents;

   return size * nmemb;
}


void getblockcount(std::string user, std::string pw){
   CURL *curl;
   CURLcode res;
   struct curl_slist *list = NULL;
   curl = curl_easy_init();

   struct MemoryStruct chunk;
   chunk.cont = "";

   curl_easy_setopt(curl, CURLOPT_URL, "http://127.0.0.1:8332");
   
   list = curl_slist_append(list, "content-type: text/plain;");
   curl_easy_setopt(curl, CURLOPT_HTTPHEADER, list);
   curl_easy_setopt(curl, CURLOPT_USERPWD, user + ":" + pw);

   std::string json_req = "{\"jsonrpc\": \"1.0\", \"id\": \"curltest\", \"method\": \"getblockcount\", \"params\": []}";

   curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, (long) json_req.length());
   curl_easy_setopt(curl, CURLOPT_POSTFIELDS, json_req.c_str());

   curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteMemoryCallback);
   curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *)&chunk);
   res = curl_easy_perform(curl);

   std::cout << "chunksize = " << chunk.cont.length() << std::endl;
   std::cout << "answer =" << chunk.cont<< std::endl;

   /* Check for errors */
   if(res != CURLE_OK){
      std::cerr << "curl_easy_perform() failed: " << curl_easy_strerror(res) << std::endl;
   }else{
      std::cout << "curl was a success" << std::endl;
   }
   curl_slist_free_all(list);

   curl_easy_cleanup(curl);
}

int main(int argc, char** argv){
   curl_global_init(CURL_GLOBAL_ALL);
   getblockcount("user", "pw");
   curl_global_cleanup();
   return 0;
}

results in

chunksize = 0
answer =
curl was a success

I am replicating the same call with the same underlying library. Why don't i get the result? What am I missing?