the_contet() problem …

im working in a new theme first time.
andy make a single.php with these code below

<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
      <h1><?php the_title(); ?></h1>
      <em><?php the_author(); ?></em>
      <p>
        <?php the_content(); ?>
      </p>
      <?php endwhile;else: ?>
     <p><?php _e('Sorry, no posts matched your criteria.'); ?></p>
     <?php endif; ?>

but it just display title and author name but the CONTENT.
any help ?