Не удается вытащить данные, отфильтровать

<?php
 
$host = 'локал';
$database = 'бд';
$user = 'юзер';
$password = 'пасс';
 
$link = mysqli_connect($host, $user, $password, $database) or die("Ошибка " . mysqli_error($link));
 
$res1 = mysqli_fetch_assoc(mysqli_query($link, "SELECT SUM(meta_value) summa1 FROM wp_postmeta WHERE meta_key = 'subsidiya'"));
 
 $var = $res1['summa1'];
 
    $number = $res1['summa1'];
    $itogo = number_format($number, 2, ",", " ");
    echo "Итого: $itogo";
 
mysqli_close($link);
?>

WHERE meta_key = 'subsidiya' AND meta_value = '2021'

$mysqli = new mysqli($host, $user, $password, $database);
 
$array_post_id = [];
 
$query = "SELECT post_id FROM wp_postmeta WHERE meta_key = 'year_kassa' AND meta_value = '2021'";
$result = $mysqli->query($query);
 
while ($row = $result->fetch_assoc()) {
    $array_post_id[] = $row['post_id'];
}
 
if(!empty($array_post_id)){
    $query = "SELECT SUM(meta_value) summa1 FROM wp_postmeta WHERE meta_key = 'subsidiya' AND post_id IN(" . implode(',', $array_post_id) . ")";
    $result = $mysqli->query($query);
}
 
 $var = $res1['summa1'];
 
    $number = $res1['summa1'];
    $itogo = number_format($number, 2, ",", " ");
    echo "Итого: $itogo";
 
$mysqli->close();
?>

 $res1 = $mysqli->query($query);

<?php
 
$host = 'локал';
$database = 'бд';
$user = 'юзер';
$password = 'пасс';
 
$mysqli = new mysqli($host, $user, $password, $database);
 
$res1 = mysqli_fetch_assoc(mysqli_query($mysqli, "SELECT SUM(a.meta_value) FROM wp_postmeta a JOIN wp_postmeta b USING(post_id) WHERE b.meta_key = 'year_kassa' AND b.meta_value = 2021 AND a.meta_key = 'subsidiya'"));
 
$var = $res1['summa1'];
 
$number = $res1['summa1'];
$itogo = number_format($number, 2, ",", " ");
echo "Итого: $itogo";
 
$mysqli->close();
?>