diff --git a/Entity/Builder.php b/Entity/Builder.php
index 0c66b75..680157b 100644
--- a/Entity/Builder.php
+++ b/Entity/Builder.php
@@ -28,7 +28,7 @@ public function create(
         array $relationships = []
     )
     {
-        return isset($builders[$resourceType])
+        return isset($this->builders[$resourceType])
             ? $this->builders[$resourceType]->create($fields, $relationships)
             : $this->builders['default']->create($fields, $relationships);
     }
diff --git a/Entity/Deleter.php b/Entity/Deleter.php
index e690264..0d353c6 100644
--- a/Entity/Deleter.php
+++ b/Entity/Deleter.php
@@ -25,7 +25,7 @@ class Deleter
      */
     public function delete($resourceType, ResourceEntityInterface $entity)
     {
-        return isset($deleters[$resourceType])
+        return isset($this->deleters[$resourceType])
             ? $this->deleters[$resourceType]->delete($entity)
             : $this->deleters['default']->delete($entity);
     }
diff --git a/Entity/Mutator.php b/Entity/Mutator.php
index 73fd073..7f6aef3 100644
--- a/Entity/Mutator.php
+++ b/Entity/Mutator.php
@@ -33,7 +33,7 @@ public function update(
         array $relationships = []
     )
     {
-        return isset($mutators[$resourceType])
+        return isset($this->mutators[$resourceType])
             ? $this->mutators[$resourceType]
                 ->update($entity, $fields, $relationships)
             : $this->mutators['default']