diff --git a/src/Form/ConfigNotifySettingsForm.php b/src/Form/ConfigNotifySettingsForm.php
index 1bb1a87e24b0bd8d4b3797b38fd8627146ef8feb..8b865ffcdc4071dd61e03881f5b0abbbb834af6e 100644
--- a/src/Form/ConfigNotifySettingsForm.php
+++ b/src/Form/ConfigNotifySettingsForm.php
@@ -8,6 +8,9 @@ use Drupal\Core\Url;
 use Drupal\Core\Link;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Drupal\config_notify\NotifierService;
+use Drupal\Core\Messenger\MessengerInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Datetime\DateFormatterInterface;
 
 /**
  * Settings form for config_notify.
@@ -21,14 +24,44 @@ class ConfigNotifySettingsForm extends ConfigFormBase {
    */
   protected $notifier;
 
+  /**
+   * Drupal\Core\Messenger\MessengerInterface definition.
+   *
+   * @var \Drupal\Core\Messenger\MessengerInterface
+   */
+  protected $messenger;
+
+  /**
+   * Drupal\Core\Extension\ModuleHandlerInterface definition.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * Drupal\Core\Datetime\DateFormatterInterface definition.
+   *
+   * @var \Drupal\Core\Datetime\DateFormatterInterface
+   */
+  protected $dateFormatter;
+
   /**
    * Constructs the object.
    *
    * @param \Drupal\config_notify\NotifierService $notifier
    *   The notifier service.
+   * @param \Drupal\Core\Messenger\MessengerInterface $messenger
+   *   The messenger service.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler service.
+   * @param \Drupal\Core\Datetime\DateFormatterInterface $date_formatter
+   *   The date formatter service.
    */
-  public function __construct(NotifierService $notifier) {
+  public function __construct(NotifierService $notifier, MessengerInterface $messenger, ModuleHandlerInterface $module_handler, DateFormatterInterface $date_formatter) {
     $this->notifier = $notifier;
+    $this->messenger = $messenger;
+    $this->moduleHandler = $module_handler;
+    $this->dateFormatter = $date_formatter;
   }
 
   /**
@@ -36,7 +69,10 @@ class ConfigNotifySettingsForm extends ConfigFormBase {
    */
   public static function create(ContainerInterface $container) {
     return new static(
-      $container->get('config_notify.notifier')
+      $container->get('config_notify.notifier'),
+      $container->get('messenger'),
+      $container->get('module_handler'),
+      $container->get('date.formatter')
     );
   }
 
@@ -61,16 +97,15 @@ class ConfigNotifySettingsForm extends ConfigFormBase {
    */
   public function buildForm(array $form, FormStateInterface $form_state) {
     $config = $this->config('config_notify.settings');
-    $messenger = \Drupal::messenger();
 
     $changes = $this->notifier->checkChanges();
     if ($changes) {
       $message = $this->t('There are configuration changes.');
-      $messenger->addMessage($message, 'warning');
+      $this->messenger->addMessage($message, 'warning');
     }
     else {
       $message = $this->t('There are no configuration changes.');
-      $messenger->addMessage($message, 'status');
+      $this->messenger->addMessage($message, 'status');
     }
 
     $form['notification_frequency'] = [
@@ -93,7 +128,7 @@ class ConfigNotifySettingsForm extends ConfigFormBase {
 
     $last_sent = $this->notifier->getLastNotificationSent();
     if ($last_sent) {
-      $date = \Drupal::service('date.formatter')->format($last_sent);
+      $date = $this->dateFormatter->format($last_sent);
       $form['message'] = [
         '#markup' => '<p>' . '<strong>' . $this->t('Last notification was sent:') . '</strong> ' . $date . '</p>',
       ];
@@ -110,8 +145,7 @@ class ConfigNotifySettingsForm extends ConfigFormBase {
       '#default_value' => $config->get('email'),
     ];
 
-    $moduleHandler = \Drupal::service('module_handler');
-    if ($moduleHandler->moduleExists('slack')) {
+    if ($this->moduleHandler->moduleExists('slack')) {
       $form['slack'] = [
         '#type' => 'checkbox',
         '#title' => $this->t('Slack notification'),
@@ -173,19 +207,19 @@ class ConfigNotifySettingsForm extends ConfigFormBase {
     $config = $this->config('config_notify.settings');
     if ($config->get('slack')) {
       if ($this->notifier->notifySlack($message)) {
-        \Drupal::messenger()->addMessage($this->t('Slack: Message was successfully sent.'));
+        $this->messenger->addMessage($this->t('Slack: Message was successfully sent.'));
       }
       else {
-        \Drupal::messenger()->addMessage($this->t('Slack: Message not sent. Please check log messages for details'), 'warning');
+        $this->messenger->addMessage($this->t('Slack: Message not sent. Please check log messages for details'), 'warning');
       }
     }
 
     if ($config->get('email')) {
       if ($this->notifier->notifyEmail($message)) {
-        \Drupal::messenger()->addMessage($this->t('Email: Message was successfully sent.'));
+        $this->messenger->addMessage($this->t('Email: Message was successfully sent.'));
       }
       else {
-        \Drupal::messenger()->addMessage($this->t('Email: Message not sent. Please check log messages for details'), 'warning');
+        $this->messenger->addMessage($this->t('Email: Message not sent. Please check log messages for details'), 'warning');
       }
     }