Checking for cookies after assigning them?

Question

JavaScript

I have a window which, after opening, sets cookies, but after closing it, it can open again even if there are conditions for the presence of cookies. How to make a check so that everything happens in real time, that is, without reloading the page?

function getCookie(name) {
  var matches = document.cookie.match(new RegExp(
    "(?:^|; )" + name.replace(/([\.$?*|{}\(\)\[\]\\\/\+^])/g, '\\$1') + "=([^;]*)"
  ));
  return matches ? decodeURIComponent(matches[1]) : undefined;
}

var alertwin = getCookie("alertwin");
if (alertwin != "no") {
  $(document).mouseleave(function (e) {
    if (e.clientY < 10) {
      $(".pop-up-exit-wrapper").fadeIn("fast");
      $(".bg-flt").fadeIn("fast");
      var date = new Date;
      date.setDate(date.getDate() + 1);
  
    }
  });

}

$(".close-btn,.bg-flt").on('click', function () {
  $('.pop-up-exit-wrapper,.bg-flt,.pop-up-timer-wrapper').fadeOut();
  document.cookie = "alertwin=no; path=/; expires=" + date.toUTCString();
})