diff --git a/src/Entity/WrapperEntityBase.php b/src/Entity/WrapperEntityBase.php
index 37a786ed66c8109c7db17c61dbc2aa01fc7e80e0..d601fa17ee5d4d5441d384f6ac4a239cb6f9efb3 100644
--- a/src/Entity/WrapperEntityBase.php
+++ b/src/Entity/WrapperEntityBase.php
@@ -111,7 +111,7 @@ abstract class WrapperEntityBase extends ConfigEntityBase implements EntityWithP
   /**
    * {@inheritdoc}
    */
-  public function access($operation, AccountInterface $account = NULL, $return_as_object = FALSE) {
+  public function access($operation, ?AccountInterface $account = NULL, $return_as_object = FALSE) {
     if ($operation == "update" || $operation == "delete") {
       $info = $this->getPluginDefinition();
       if (!empty($info['locked'])) {