所以我正在尝试发送电子邮件通知办公室管理员何时通过表单提交电子邮件。当我使用以“.com”结尾的电子邮件时，一切都没有问题但是，当我尝试使用以“.org”结尾的电子邮件时
$first_name = $_POST['first_name'];
$last_name = $_POST['last_name'];
$email_address = $_POST['email_address'];
$message = $_POST['message'];
if(isset($_POST['submit'])){
$to = "officeadmin@example.org"; // Office Admin Email
$from = $email_address; // User's Email
$subject = "Form Submission";
$content_admin = $first_name . " " . $last_name . " wrote the following:" . "\n\n" . $message;
$content_user = "Thanks again for contacting us. A dedicated staff member will contact you as soon as possible. Your message was: \n\n" . $message;
$headers_admin = "From:" . $from;
$headers_user = "From: Example Office";
mail($to,$subject,$content_admin,$headers_admin); //Notification email for admin
mail($from,'Thanks for contacting us',$content_user, $headers_user); //Copy of email sent to user
header('Location: contact_form_success.html'); //Redirect here after submit is clicked
}