title: If (is_page_template()) not working in header.php
body: <p>I have 3 separate header options, all with a banner image:
  1. Homepage
  2. Sponsor Template
  3. All other pages.</p>
  
  <p>I have placed the below code in the header. The homepage and all other pages are working as expected, but I can't seem to make the Sponsor template work (the class="sponsor-title" is not appearing).</p>
  
  <pre><code>&lt;?php if ( has_post_thumbnail()) : ?&gt;
      &lt;?php the_post_thumbnail(); ?&gt;
  &lt;?php endif; ?&gt;
  &lt;?php if ( is_front_page()): ?&gt;
      &lt;span class="home"&gt;&lt;h1&gt;&lt;?php echo event_title(); ?&gt;&lt;/h1&gt;&lt;/span&gt;
      &lt;span class="tag-line"&gt;&lt;?php the_field('tag_line'); ?&gt;&lt;/span&gt;
      &lt;span class="date"&gt;&lt;?php the_field('date_time_header'); ?&gt;&lt;/span&gt;
      &lt;?php 
          $ticket = get_field('ticket_url');
          if ( $ticket ): 
              $ticket_url = $ticket['url'];
              $ticket_title = $ticket['title'];
          ?&gt;
          &lt;a class="button" href="&lt;?php echo esc_url($ticket_url); ?&gt;"&gt;&lt;?php echo esc_html($ticket_title); ?&gt;&lt;/a&gt;
  &lt;?php if (!is_page_template('page-templates/all-sponsor-template.php')); ?&gt;
      &lt;span class="sponsor-title"&gt;&lt;h1&gt;&lt;?php echo event_title(); ?&gt;&lt;/h1&gt;&lt;/span&gt;
  &lt;?php endif; ?&gt;
  &lt;?php else: ?&gt;
      &lt;span class="page-title"&gt;&lt;h1&gt;&lt;?php the_field('page_header'); ?&gt;&lt;/h1&gt;&lt;/span&gt;
      &lt;span class="sub-header"&gt;&lt;?php the_field('sub_header'); ?&gt;&lt;/span&gt;
  &lt;?php endif;?&gt; 
  </code></pre>
  
  <p>What have I done wrong? I want to ensure that when the template or page is chosen that the correct styling appears, as it is very different from the other pages.</p>