diff --git a/src/Plugin/Validation/Constraint/TweetVisibleConstraintValidator.php b/src/Plugin/Validation/Constraint/TweetVisibleConstraintValidator.php
index ccf13fe..81967da 100644
--- a/src/Plugin/Validation/Constraint/TweetVisibleConstraintValidator.php
+++ b/src/Plugin/Validation/Constraint/TweetVisibleConstraintValidator.php
@@ -3,9 +3,11 @@
 namespace Drupal\media_entity_twitter\Plugin\Validation\Constraint;
 
 use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
+use Drupal\Core\Field\FieldItemListInterface;
 use Drupal\media_entity_twitter\Plugin\media\Source\Twitter;
 use Drupal\Core\Field\FieldItemInterface;
 use GuzzleHttp\Client;
+use GuzzleHttp\Exception\ClientException;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\Validator\Constraint;
 use Symfony\Component\Validator\ConstraintValidator;
@@ -47,7 +49,7 @@ class TweetVisibleConstraintValidator extends ConstraintValidator implements Con
     if (is_string($value)) {
       $data = $value;
     }
-    elseif ($value instanceof FieldItemList) {
+    elseif ($value instanceof FieldItemListInterface) {
       $fieldtype = $value->getFieldDefinition()->getType();
       $field_value = $value->getValue();
       if ($fieldtype == 'link') {
@@ -76,7 +78,13 @@ class TweetVisibleConstraintValidator extends ConstraintValidator implements Con
     }
 
     // Fetch content from the given url.
-    $response = $this->httpClient->get($matches[0][0], ['allow_redirects' => FALSE]);
+    try {
+      $response = $this->httpClient->get($matches[0][0], ['allow_redirects' => FALSE]);
+    }
+    catch (ClientException $e) {
+      $this->context->addViolation($constraint->message);
+      return;
+    }
 
     if ($response->getStatusCode() == 302 && ($location = $response->getHeader('location'))) {
       $effective_url_parts = parse_url($location[0]);
diff --git a/tests/src/Functional/TweetEmbedFormatterTest.php b/tests/src/Functional/TweetEmbedFormatterTest.php
index ebbc13b..9f07028 100644
--- a/tests/src/Functional/TweetEmbedFormatterTest.php
+++ b/tests/src/Functional/TweetEmbedFormatterTest.php
@@ -107,7 +107,7 @@ class TweetEmbedFormatterTest extends MediaFunctionalTestBase {
     $this->drupalGet('media/add/' . $bundle->id());
 
     // Random image url from twitter.
-    $tweet_url = 'https://twitter.com/RamzyStinson/status/670650348319576064';
+    $tweet_url = 'https://twitter.com/DrupalConEur/status/1176518741208817664';
 
     // Random image from twitter.
     $tweet = '<blockquote class="twitter-tweet" lang="it"><p lang="en" dir="ltr">' .
@@ -130,7 +130,7 @@ class TweetEmbedFormatterTest extends MediaFunctionalTestBase {
 
     // Assert that the link url formatter exists on this page.
     $this->assertText('Tweet URL');
-    $this->assertRaw('<a href="https://twitter.com/RamzyStinson/statuses/670650348319576064">', 'Link in embedded Tweet found.');
+    $this->assertRaw('<a href="https://twitter.com/DrupalConEur/statuses/1176518741208817664">', 'Link in embedded Tweet found.');
 
     // Assert that the string_long code formatter exists on this page.
     $this->assertText('Embed code');