Не ожидаемый результат GET запроса на сервер

string client::getResponse()
{
    boost::asio::io_context ioc;
    boost::asio::ip::tcp::resolver resolver(ioc);
    boost::asio::ip::tcp::socket socket(ioc);
    string argument = API_ARGUMENTS;
    boost::asio::connect(socket, resolver.resolve(MAIN_API, "80"));
    http::request<http::string_body> req(http::verb::get, argument, 11);
    req.set(http::field::host, MAIN_API);
    req.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING);
    http::write(socket, req);
    string response;
    {
        boost::beast::flat_buffer buffer;
        http::response<http::dynamic_body> res;
        http::read(socket, buffer, res);
        response = boost::beast::buffers_to_string(res.body().data());
    }
    socket.shutdown(boost::asio::ip::tcp::socket::shutdown_both);
    return response;
}

#include <iostream>
#include "dweuro_header.h"
using std::cout;
using std::endl;
int main()
{
    client obj;
    obj.set_API("dw.euro.who.int","/api/v3/version/"); //To access the API use https://dw.euro.who.int // To get current version of the API use the following URL: /api/v3/version.
    string responsestr = obj.getResponse();                                               ( c добавлением https:// результат не меняется )
    cout << responsestr << endl;
}