Rerun Function on page load.

Hi,

I think I have a simple one. I’m new to Drupal 8 and have been playing around with creating custom modules and blocks. I created the below block that reads in the id variable from the url. I would like to have it update when the page loads. So for example the URL to the page is /node/Team and I pass the variable id like /node/Team?id=* where, * is 0,1,2,…

What ends up happening is that it work like a dream the first time the page loads, but will not update when I change the url. Anyway thank you ahead of time!

<?php
namespace Drupalnationalteam_pagePluginBlock;

use DrupalCoreBlockBlockBase;
use DrupalCoreBlockBlockPluginInterface;

use DrupalCoreUrl;
use DrupalCoreLink;

/**
 * Provides a 'Hello' Block.
 * @Block(
 *   id = "_block_national",
 *   admin_label = @Translation("Team Stats"),
 * )
 */
class NationalTeamBlock extends BlockBase{

  /**
   * {@inheritdoc}
   */
  public function build() {
	 
	return array(
      '#markup' => $this->t( $_GET["id"]),
    );
  }

And URL’s look like:
node/Teams?id=0, node/Teams?id=1, node/Teams?id=2, …

Drupal version: 


Source: https://www.drupal.org/taxonomy/term/22/feed