How to fix the encoding of the subject?

//event on change order
AddEventHandler("sale", "OnOrderAdd", "onOrderCreateHandler");
onOrderCreateHandler function($ID, $arFields){
$messagetext = 'Hello! Customer made new order';
$messagetop = mb_convert_encoding('New online ordering website SHOP', 'utf-8', mb_detect_encoding('New online ordering website SHOP'));
$headers = 'From: SHOP <robot@test.ru>' . "\r\n" .
 'Reply-To: robot@test.ru' . "\r\n" .
 'Bcc: man@test.ru' . "\r\n" .
 'X-Mailer: PHP/' . phpversion() . 
'MIME-Version: 1.0' . "\r\n" . 
'Content-type: text/html; charset=UTF-8' . "\r\n";
 mail('info@test.ru', $messagetop, $messagetext, $headers); }

The letter comes. In Outlook, including Outlook mobile is the text of the letter is normally displayed, and the mail header $messagetop krakozyabry. In Browser - norms.
How to fix? Tried different encoding to indicate no purpose.
April 3rd 20 at 17:31
0 answer

Find more questions by tags PHP