PHP和MySQL连接失败：php_network_getaddresses：getaddrinfo失败：名称或服务未知

Question

有人知道为什么我的连接失败吗？我正在尝试连接到freeasphost.net上的现有数据库。

$servername = "sql.freeasphost.net\MSSQL2016";
    $dbname = "CorrectName";
    $username = "CorreectUsername";
    $password = "CorrectPW";
    
    if ($_SERVER["REQUEST_METHOD"] = "POST") {
            
            // Create connection
            $conn = new mysqli($servername, $username, $password, $dbname);
            // Check connection
            if ($conn->connect_error) {
                die("Connection failed: " . $conn->connect_error);
            }