<?php
if($login_incorrect){
     if(isset($_COOKIE['login'])){
          if($_COOKIE['login'] < 3){
               $attempts = $_COOKIE['login'] + 1;
               setcookie('login', $attempts, time()+60*10); //set the cookie for 10 minutes with the number of attempts stored
          } else{
               echo 'You are banned for 10 minutes. Try again later';
          }
     } else{
          setcookie('login', 1, time()+60*10); //set the cookie for 10 minutes with the initial value of 1
     }
}
?>