PHP 로그인하기에서 값을 왜 못가지고 올까요?ㅠ

<form name="login_form" action="../lib/func/func_login.php" method="post" onsubmit="return chk_logform();">

<input type="text" name="fuserid" class="form_control" placeholder="아이디를 입력해주세요.">
<input type="password" name="fpasswd" class="form_control" placeholder="비밀번호를 입력해주세요">
<input type="submit" name="submit" class="btn_default btn_green" value="로그인">
</form>

<?php
    session_start();

    $fuserid = $_POST['fuserid'];
    $fpasswd = $_POST['fpasswd'];

    $_SESSION['ses_userid'] = $fuserid;
    $_SESSION['ses_pass'] = $fpasswd;
?>

<?php
    include "../session.php";
    include "../db_conn.php";

    $sql="select * from user where id='$fuserid' and password='$fpasswd' ";
    $res=mysqli_query($conn, $sql);
    $list = mysqli_num_rows($res);

    //die($sql);
    
    if($list){
        $row = mysqli_fetch_array($res);
        $ses_userid = $row['id'];
        $ses_pass = $row['password'];
        
        echo "로그인성공";
    } else {
        echo "아이디 또는 비밀번호가 틀립니다.";
    }
?>