勾选了自动登录再打开还是显示请登录是怎么回事

doLogin.php

<?php

//session_start();

require_once '../include.php';

$username=$_POST['username'];

$password=md5($_POST['password']);

$verify=$_POST['verify'];

$verify1=$_SESSION['verify'];

$autoFlag=$_POST['autoFlag'];//自动登录

if($verify==$verify1){

    $sql="select * from imooc_admin where username='{$username}' and password='{$password}'";

    $row=checkAdmin($sql);  

    if($row){

        if($autoFlag){

            setcookie("adminId",$row['Id'],time()+7*24*3600);

            setcookie("adminName",$row['username'],time()+7*24*3600);

        }

        $_SESSION['adminId']=$row['id'];

        $_SESSION['adminName']=$row['username'];

        alertMes("登录成功","index.php");

    }else{

        alertMes("登录失败，重新登录","login.php");

    }

}else{

    alertMes("验证码错误","login.php");

}