Hi adcodingmaster,
It sounds like you are sending a plain text email.
To send it in HTML format, add this header
$headers .= "MIME-Version: 1.0" . "\r\n" . "Content-type:text/html;charset=iso-8859-1" . "\r\n";
This will add the correct text to the variable called $headers (it will not replace it). Change this variable name if needed.
Hope this helps.
Zagga