Envio de E-mails por api

Alguem poderia me ajudar , por favor,

Fatal error: Uncaught Swift_RfcComplianceException: Address in mailbox given [1615victorsamuel@gmail.com;samuel1615samuel@gmail.com ] does not comply with RFC 2822, 3.6.2. in D:\InetPub\wwwroot\scriptcase\prod\third\swift\classes\Swift\Mime\Headers\MailboxHeader.php:348 Stack trace: #0 D:\InetPub\wwwroot\scriptcase\prod\third\swift\classes\Swift\Mime\Headers\MailboxHeader.php(263): Swift_Mime_Headers_MailboxHeader->assertValidAddress(‘1615victorsamue…’) #1 D:\InetPub\wwwroot\scriptcase\prod\third\swift\classes\Swift\Mime\Headers\MailboxHeader.php(106): Swift_Mime_Headers_MailboxHeader->normalizeMailboxes(Array) #2 D:\InetPub\wwwroot\scriptcase\prod\third\swift\classes\Swift\Mime\Headers\MailboxHeader.php(63): Swift_Mime_Headers_MailboxHeader->setNameAddresses(Array) #3 D:\InetPub\wwwroot\scriptcase\prod\third\swift\classes\Swift\Mime\SimpleHeaderFactory.php(58): Swift_Mime_Headers_MailboxHeader->setFieldBodyModel(Array) #4 D:\InetPub\wwwroot\scriptcase\prod\third\swift\classes\Swift\Mime\SimpleHeaderSet.php(68): Swift in D:\InetPub\wwwroot\scriptcase\prod\third\swift\classes\Swift\Mime\Headers\MailboxHeader.php on line 348

meu codigo
{api_type}='smtp';

$smtp_server = “mail.email_serve”;
$smtp_port = “port”;
$smtp_user = “email@user.com”;
$smtp_password = “senha”;
$from_email = “email@user.com”;
$from_name = “name_Contato”;
$msg = “{conteudo}”;
$to = “{to}”;
$subject = “{subject}”;

if ( {api_type} == ‘smtp’ ){
$var_config = array(

	'profile' => 'name_api',


	
	
	
	
'settings' => [
		   'gateway'		=> 'smtp',
		   'smtp_server'	=> $smtp_server,
		   'smtp_port'		=> $smtp_port,
		   'smtp_user'		=> $smtp_user,
		   'smtp_password'	=> $smtp_password,
		   'from_email'		=> $from_email,
		   'from_name'		=> $from_name
		  ],

	'message' => [
			   'html'          => $msg,
			   'text'          => '',
			   'to'            => $to,
			   //'attachments' => array('/var/www/arquivo.txt','/var/www/arquivo2.txt'),
			   'subject'       => {subject}
	]
);

}

sc_send_mail_api($var_config);

Este 1615 fazem parte mesmo do email?

Se enviar com um email só funciona?

outra coisa, pode ser que esta separando com ; (ponto e virgula) tenta colocar com , (virgula)