Why PHP is not showing my HTML code inside an "if" statement? [on hold]

I'm trying to create a forgot password page and I have echoed some HTML into my PHP code but the HTML part is not showing

code:

if(!$_GET['code']) {
  echo "
    <form action='forgot_pass.php' method='POST'>
      Enter your username<br><input type='text' name='username'><p>
      Enter your email<br><input type='text' name='email'><p>
      <input type='submit' value='Submit' name='submit'>
    </form>
  ";
}