Run-time check failure #2 - Stack around the variable 'root' was corrupted

Question

Basically doing this simple request i get an error that says: enter image description here : Run-time check failure #2 - Stack around the variable 'root' was corrupted. What could it be? My code basically just as the binance server for the time and then print it, I'm new to c++ so these are just some tests :

#include <iostream>
#include <curl/curl.h>
#include "json/json.h"
#include "json/reader.h"
#include "json/writer.h"
#include "json/value.h"

size_t WriteCallback(char* contents, size_t size, size_t nmemb, void* userp)
{
    ((std::string*)userp)->append((char*)contents, size * nmemb);
    return size * nmemb;
}

int main()
{
    
    CURL* curl;
    CURLcode res;
    std::string readBuffer;
    Json::Value root;
    Json::Reader reader;
    

    curl = curl_easy_init();
    if (curl) {
    
        curl_easy_setopt(curl, CURLOPT_URL, "https://api.binance.com/api/v3/time");
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteCallback);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &readBuffer);

        CURLcode res = curl_easy_perform(curl);

        bool parsingSuccessful = reader.parse(readBuffer.c_str(), root);     //parse process
        if (!parsingSuccessful)
        {
            std::cout << "Failed to parse"
                << reader.getFormattedErrorMessages();
            return 0;
        }
        std::cout << root.get("serverTime","").asString() << std::endl;

        
        curl_easy_cleanup(curl);
    }
    
    return 0;
}