diff --git a/plugin.php b/plugin.php
index ebd49ba1..0e65507f 100644
--- a/plugin.php
+++ b/plugin.php
@@ -6,7 +6,7 @@
  * Description: Enable blocks in WP GraphQL.
  * Author: pristas-peter
  * Author URI:
- * Version: 0.3.7
+ * Version: 0.3.8
  * Requires at least: 5.4
  * License: GPL-3
  * License URI: https://www.gnu.org/licenses/gpl-3.0.html
diff --git a/src/Schema/Types/Scalar/Scalar.php b/src/Schema/Types/Scalar/Scalar.php
index d4c65595..d7eb1fe7 100644
--- a/src/Schema/Types/Scalar/Scalar.php
+++ b/src/Schema/Types/Scalar/Scalar.php
@@ -4,7 +4,7 @@
 
 class Scalar {
 	public function __construct() {
-		add_action('graphql_register_types', function ($type_registry) {
+		add_action('graphql_register_types_late', function ($type_registry) {
 			register_graphql_scalar('BlockAttributesObject', [
 				'serialize' => function ($value) {
 					return json_encode($value);