PHPmailer正在将副本发送到我的电子邮件中

当我通过PHPmailer（SMTP）发送测试消息时，我的电子邮件会附加到收件人列表中。以下是收件人在收件箱电子邮件中看到的内容

收件人：mail@mail.com，名称<mail2@mail.com>

第二封电子邮件是我的。我该怎么阻止？

这是我的代码

function send_email($to, $fromName, $subject, $message, $contentType='text', $smtp_opts) {
    $mail = new PHPmailer();
    $mail->SetFrom($smtp_opts['fromEmail'], $fromName);
    $mail->Subject = $subject;
    $mail->Mailer = 'smtp';
    $mail->AddAddress($to);
    $mail->CharSet = "UTF-8";
    $mail->IsHTML($contentType=='html');
    $mail->Host = $smtp_opts['host'];
    $mail->SMTPAuth = (bool)$smtp_opts['auth'];
    if ($mail->SMTPAuth) {
        $mail->Username = $smtp_opts['username'];
        $mail->Password = $smtp_opts['password'];
    }
    $mail->Body = $message;
    $mail->AddAddress($smtp_opts['fromEmail'], $fromName);
    $result = $mail->Send();
    $mail->ClearAddresses();
    $mail->ClearAttachments();
    return $result;
}
$smtp_opts = array( ... ); // host, port, fromEmail, auth, username, password
send_email('mail@mail.com', 'Name', 'Subj', 'Msg', 'html', $smtp_opts);