the plugin does not detect my comments

Hello, the plugin does not detect my comments form, how can I add the recaptcha to the comments manually?

<p>
<input type="text" name="author" id="author" class="textarea" value="<?php echo $comment_author; ?>" size="28" tabindex="1" />
<label for="author"><?php _e('Name'); ?></label> <?php if ($req) _e('*'); ?>
</p>
<p>
<input type="text" name="email" id="email" value="<?php echo $comment_author_email; ?>" size="28" tabindex="2" class="textarea" />
<label for="email"><?php _e('E-mail'); ?></label> <?php if ($req) _e('*'); ?>
</p>
<p>
<input type="text" name="url" id="url" value="<?php echo $comment_author_url; ?>" size="28" tabindex="3" class="textarea" />
<label for="url"><?php _e('WEB (opcional)'); ?></label>
</p>

<?php do_action( 'wordpress_social_login' ); ?>
<?php endif; ?>
<p>
<textarea name="comment" id="comment" cols="60" rows="10" tabindex="4" class="textarea"></textarea>
</p>
<p>
<input name="submit" id="submit" type="submit" tabindex="5" value="<?php _e('Enviar Comentario'); ?>" class="Cbutton" /><br>
Notificaciones: <?php global $wp_subscribe_reloaded; if (isset($wp_subscribe_reloaded)){ $wp_subscribe_reloaded->stcr->subscribe_reloaded_show(); } ?>
<?php comment_id_fields(); ?>
</p>