Below is an error message. The code works on a different website, but when I used it in another website and changed the column names the variable were undefined?  I tried to research before I asked.  I used isset and content=
still no luck.  
Notice: Undefined variable: film in /Applications/XAMPP/xamppfiles/htdocs/movies/films.php on line 168
<?php if( !empty($_GET['action']) && $_GET['action'] == "edit" ) { ?>
                <legend>Editing Film Listing</legend>
                <form name="frmEditFilm" action="films.php?action=edit" method="POST">
                    <input type="hidden" name="film_id" value="<?php echo $film['film_id']; ?>">
                    <label for="film_title">Film Title</label>
                    <input type="text" name="film_title" class="form-control" value="<?php echo $film['title']; ?>">
                    <label for="film_release">Film Release</label>
                    <input type="text" name="film_release" class="form-control" value="<?php echo $film['release_year']; ?>">
                    <label for="film_description">Film Description</label>
                    <textarea name="film_description" class="form-control"/><?php echo $film['description']; ?></textarea>
                    <button type="submit" class="btn btn-info">Update Film</button>
                </form>
            <?php } ?>
 
    