New Post: Casablanca Concurrency Error

    http_client client(LOGIN_SERVICE_URL);
    uri_builder builder(OAUTH2_CONTEXT_PATH);
    
builder.append_query(L"grant_type", L"password");
builder.append_query(L"username", username);
    builder.append_query(L"password", password);
    builder.append_query(L"scope", L"send_hybrid");

    http_request request(methods::POST);
    request.headers().add(L"Authorization", AUTH_STRING);
    request.headers().add(L"content-type", L"application/x-www-form-urlencoded");
    request.set_request_uri(builder.to_uri());

    client.request(request);

cpprest120d_xp_2_1.dll!Concurrency::details::_ExceptionHolder::~_ExceptionHolder(void)  Unknown
cpprest120d_xp_2_1.dll!Concurrency::details::_ExceptionHolder::`scalar deleting destructor'(unsigned int)   Unknown
cpprest120d_xp_2_1.dll!std::_Ref_count_obj<struct Concurrency::details::_ExceptionHolder>::_Destroy(void)   Unknown
cpprest120d_xp_2_1.dll!std::_Ref_count_base::_Decref(void)  Unknown
cpprest120d_xp_2_1.dll!std::_Ptr_base<struct Concurrency::details::_ExceptionHolder>::_Decref(void) Unknown
cpprest120d_xp_2_1.dll!std::shared_ptr<struct Concurrency::details::_ExceptionHolder>::~shared_ptr<struct Concurrency::details::_ExceptionHolder>(void) Unknown
cpprest120d_xp_2_1.dll!Concurrency::details::_Task_completion_event_impl<class web::http::http_response>::~_Task_completion_event_impl<class web::http::http_response>(void)    Unknown
cpprest120d_xp_2_1.dll!Concurrency::details::_Task_completion_event_impl<class web::http::http_response>::`scalar deleting destructor'(unsigned int)    Unknown
cpprest120d_xp_2_1.dll!std::_Ref_count_obj<struct Concurrency::details::_Task_completion_event_impl<class web::http::http_response> >::_Destroy(void)   Unknown
cpprest120d_xp_2_1.dll!std::_Ref_count_base::_Decref(void)  Unknown
cpprest120d_xp_2_1.dll!std::_Ptr_base<struct Concurrency::details::_Task_completion_event_impl<class web::http::http_response> >::_Decref(void) Unknown
cpprest120d_xp_2_1.dll!std::shared_ptr<struct Concurrency::details::_Task_completion_event_impl<class web::http::http_response> >::~shared_ptr<struct Concurrency::details::_Task_completion_event_impl<class web::http::http_response> >(void) Unknown
cpprest120d_xp_2_1.dll!Concurrency::task_completion_event<class web::http::http_response>::~task_completion_event<class web::http::http_response>(void) Unknown
cpprest120d_xp_2_1.dll!web::http::client::details::request_context::~request_context(void)  Unknown
cpprest120d_xp_2_1.dll!web::http::client::details::winhttp_request_context::~winhttp_request_context(void)  Unknown
cpprest120d_xp_2_1.dll!web::http::client::details::winhttp_request_context::`vector deleting destructor'(unsigned int)  Unknown
cpprest120d_xp_2_1.dll!web::http::client::details::winhttp_request_context::finish(void)    Unknown
cpprest120d_xp_2_1.dll!web::http::client::details::request_context::report_exception(class std::exception_ptr)  Unknown
cpprest120d_xp_2_1.dll!web::http::client::details::request_context::report_exception<class web::http::http_exception>(class web::http::http_exception)  Unknown
cpprest120d_xp_2_1.dll!web::http::client::details::request_context::report_error(unsigned long,class std::basic_string<wchar_t,struct std::char_traits<wchar_t>,class std::allocator<wchar_t> > const &)    Unknown
cpprest120d_xp_2_1.dll!web::http::client::details::winhttp_client::completion_callback(void *,unsigned long,unsigned long,void *,unsigned long) Unknown
winhttp.dll!73f34b87()  Unknown
[Frames below may be incorrect and/or missing, no symbols loaded for winhttp.dll]   
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