PHP联系表格不断收到垃圾邮件

Question

我的联系表单每天都会收到垃圾邮件。不知道为什么。这是contact-process.php来处理提交：

            <?php

            // configure
            $from = 'webmaster@example.com'; 
            $sendTo = 'Message from <myemail@mydomain.com>';
            $subject = "Contact Form: $name";
            $fields = array('name' => 'Name', 'surname' => 'Surname', 'phone' => 'Phone', 'email' => 'Email', 'message' => 'Message'); // array variable name => Text to appear in the email
            $human = intval($_POST['humans']);
            $okMessage = 'Contact form successfully submitted. Thank you, I will get back to you soon!';
            $errorMessage = 'There was an error while submitting the form. Please try again later';
            $headers = 'From: webmaster@example.com' . "\r\n" .
                'Reply-To: webmaster@example.com' . "\r\n" .
                'X-Mailer: PHP/' . phpversion();
            // let's do the sending

            try
            {
                $emailText = "You have new message from contact form\n=============================\n";

                foreach ($_POST as $key => $value) {

                    if (isset($fields[$key])) {
                        $emailText .= "$fields[$key]: $value\n";
                    }
                }


                mail($sendTo, $subject, $emailText, implode("\n", $headers));

                $responseArray = array('type' => 'success', 'message' => $okMessage);

                    header('Location: /thank-you.php');
            }
            catch (\Exception $e)
            {
                $responseArray = array('type' => 'danger', 'message' => $errorMessage);
            }

            if (!empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest') {
                $encoded = json_encode($responseArray);

                header('Content-Type: application/json');

                echo $encoded;
            }
            else {
                echo $responseArray['message'];
            }


            //Check if simple anti-bot test is correct
            if(!empty($_POST['humans'])) {
                // it's spam
            } else {
                // it's human
            }

我不知道为什么会这样，我也设置了一个蜜罐。此外，电子邮件是从主机名发送的，而不是从各个电子邮件地址本身发送的。

感谢帮助人员。