How to remove “Archive:” label from archive title

I need to remove “Archive:” label from the archive page title.
I tried this string without results:

<?php the_archive_title('<h2>','</h2>', false);?>

The title keeps displaying the “Archive:” label before the title.
How can I get rid of it?

This is the full code of my page:

<?php get_header('inner');?>

    <div class="row large-uncollapse">
        <div class="columns small-12 medium-12 large-12">
            <div class="breadcrumbs" typeof="BreadcrumbList" vocab="http://schema.org/">

              <?php if(function_exists('bcn_display'))
              {

                echo '<b>Sei in:</b>';
                bcn_display();
              }?>
            </div>

        </div>
    </div>

    <div class="row large-uncollapse">
        <div class="columns small-12 medium-12 large-12 large-centered text-center pad-vr-2">
          <?php echo get_the_archive_title();?>
        </div>
    </div>

<?php if(is_singular('rassegna-stampa')): ?>

    <div id="rassegna-stampa">
        <div class="row large-collapse">

          <?php
          if ( have_posts() ) :
            while ( have_posts() ) : the_post();
              echo '<div class="columns small-12 medium-6 large-4 float-left" style="margin-bottom:10px;">';
              echo '<div class="columns small-3 medium-3 large-3">';
              if(has_post_thumbnail()){
                echo the_post_thumbnail();
              }
              if( get_field('file') ) {
                echo '<a href="';
                the_field('file');
                echo '" data-featherlight="iframe" target="_blank">';
                echo '<button>';
                echo '<img src="';
                echo get_site_url();
                echo '/wp-content/uploads/2016/09/pdf.png" width="20px">';
                echo '</button>';
                echo '</a>';
              }
              if( get_field('link') ) {
                echo '<a href="';
                echo the_field('link');
                echo '" data-featherlight="iframe">';
                echo '<button>';
                echo '<img src="';
                echo get_site_url();
                echo '/wp-content/uploads/2016/09/link.png" width="20px">';
                echo '</button>';
                echo '</a>';
              }
              echo '</div>';
              echo '<div class="columns small-9 medium-9 large-9">';
              echo '<h3 style="margin:0px;">';
              echo the_title();
              echo '</h3>';
              echo '<small>';
              echo '—';
              echo the_field('testata');
              echo '</small>';
              echo '<small>';
              echo the_field('data');
              echo '</small>';
              echo '<span style="font-size:12px;">';
              the_excerpt();
              echo '</span>';
              echo '</div>';
              echo '</div>';
            endwhile;
          else :
            echo wpautop( 'Sorry, no posts were found' );
          endif;
          ?>
        </div>
    </div>


<?php else :?>

    <div id="libri">
        <div class="row large-collapse">

          <?php
          if ( have_posts() ) :
            while ( have_posts() ) : the_post();
              echo '<div class="columns small-12 medium-6 large-4 float-left" style="margin-bottom:10px;padding-bottom: 12px; height:220px;">';
              echo '<div class="columns small-3 medium-3 large-3">';
              if(has_post_thumbnail()){
                echo the_post_thumbnail();
              }
              echo '</div>';
              echo '<div class="columns small-9 medium-9 large-9">';
              echo '<h3 style="margin:0px;">';
              echo the_title();
              echo '</h3>';
              echo '<div style="float:left;width:100%;">';
              echo '<small style="float:left;width:auto;">';
              echo the_field('anno_pubblicazione');
              echo '</small>';
              echo '<div style="float:left; line-height:15px;">';
              echo '&nbsp;—&nbsp; ';
              echo '</div>';
              echo '<small style="float:left;width:auto;">';
              echo the_field('editore');
              echo '</small>';
              echo '</div>';
              echo '<span style="font-size:12px;">';
              the_excerpt();
              echo '</span>';
              echo '</div>';
              echo '<div class="columns small-12 medium-12 large-6">';
              echo '<a href="';
              the_permalink();
              echo '">';
              echo '<button style="width:auto; padding:0.4rem; float:left; border:1px #000 solid;">';
              echo 'Leggi tutto';
              echo '</button>';
              echo '</a>';
              echo '</div>';
              echo '<div class="columns small-12 medium-12 large-6">';
              if( get_field('link_acquisto') ):
                echo '<a href="';
                echo the_field('link_acquisto');
                echo '" style="color:#D34D3D;">';
                echo '<button style="width:auto; padding:0.4rem; float:left; border:1px #D34D3D solid;">';
                echo 'COMPRA';
                echo '</button>';
                echo '</a>';
              endif;
              echo '</div>';
              echo '</div>';
            endwhile;
          else :
            echo wpautop( 'Sorry, no posts were found' );
          endif;
          ?>
        </div>
    </div>

<?php endif ;?>

<?php get_footer();?>

Thanks!

You need to use the filter get_the_archive_title. It works like the_title filter.
More details about the function that embed the filter here

More in this question remove category tag

EDIT :

When it’s a custom post type archive page, you might use another function to print the title : post_type_archive_title()
Then you’ll be able to hook in the title with the filter post_type_archive_title , but there is no prefix for this function.

So in your template replace the call to get_the_archive_title() function with:

post_type_archive_title();