Why doesn't mail() work?

Question

PHP

Send code:

spoiler

$mail='
          <style>
.msgBody{width: 60%;margin-left: 20%;border-radius: 10px;background: #fff;color: #222;font-family: Tahoma;border: 1px solid #ebebeb;overflow: hidden;}
.msgBody .header{width: 100%;padding-top: 20px;padding-bottom: 20px;background: #2a394f;}	.msgBody .content{width: 100%;padding-top: 80px;padding-bottom: 80px;text-align: center;}
.msgBody .content .btn{width: 40%;margin-left: 30%;height: 30px;line-height: 30px;font-size: 18px;color: #fff;background: #0fa8f4;border-radius: 7px;cursor: pointer;padding-top: 20px;padding-bottom: 20px;text-align: center;margin-top: 40px;}
.msgBody .content a{text-decoration: none;}
</style>
<div class="msgBody">
  <div class="header">
    <img src="http://scs39.ru/img/logo.png" style="width: 30%; height: auto; margin-left: 35%;">		
  </div>
  <div class="content">
    '.$name.', здравствуйте!<br>
    Для активации нажмите на кнопку ниже:<br>
    <a href="http://domain.ru/activate.php?key='.$key.'&l='.$phone'"><div class="btn">Активировать аккаунт</div></a>
  </div>
</div>';
          $mail=convert_cyr_string($mail,"w","k");
          $hed="Content-Type: text/html; charset=koi8-r
          From:Автописьмо<[email protected]>
          To:  Клиент
          Subject:  Активация аккаунта
          Content-Type: text/html; charset=koi8-r";
          $hed=convert_cyr_string($hed,"w","k");					 
          mail($email,"",$mail,$hed);

I can't figure out what the problem is.

Answer 1

Show the func_reg.php code
, in the region of the 83rd line
. The closing line above is not closed, apparently

Answer 2

Problem solved.
Forgot to add a dot after .$phone