$headers = 'From: ' . $this->from_name . ' <' . $this->from_email .'>' . "rn";
wp_mail( $service->getEmail(), $this->admin_daily_subject, $admin_daily_message, $headers );

$headers = 'From: ' . $this->from_name . ' <'.$this->from_email.'>' . "rn" .
                           'Reply-To: '.$this->from_email . "rn" .
                           'X-Mailer: PHP/' . phpversion() . "rn" .
                           "Content-Type: text/html; charset=UTF-8";
mail( $service->getEmail(), $this->admin_daily_subject, $admin_daily_message, $headers );

$phpmailer->setFrom( $from_email, $from_name );

$phpmailer->setFrom( $from_email, $from_name, false );

$phpmailer->IsSMTP();
$phpmailer->Host = "smtp.example.com";
$phpmailer->Port = <SMTP PORT>;
$phpmailer->SMTPSecure = 'ssl';  //optional, can also be 'tls'
$phpmailer->SMTPAuth = true;
$phpmailer->Username = '<your smtp username>';
$phpmailer->Password = '<your smtp password>';