single.php does not work

I have in my index 3 posts and when I click to open it through a permalink it enters single.php. so far so good, the link in the browser appears calling the post, but the page goes blank.

I did so in single.php code

Calling content-single.php

    <div class="container">
        <h1><?php the_title(); ?></h1>
        <div class="row">
            <div class="col-md-6 text-left"><p>Data: <?php echo get_the_date(); ?></p></div>
            <div class="col-md-6 text-right"><p>Por: <?php the_author_posts_link(); ?></p></div>
        </div>

        <p><?php the_tags('Tags: ', ' , '); ?></p>

        <h4><?php the_excerpt(); ?></h4>
    </div>
</header>
    <div class="content"><?php the_content(); ?></div>