diff --git a/src/Storage/Field/Type/RepeaterType.php b/src/Storage/Field/Type/RepeaterType.php
index <HASH>..<HASH> 100644
--- a/src/Storage/Field/Type/RepeaterType.php
+++ b/src/Storage/Field/Type/RepeaterType.php
@@ -83,7 +83,7 @@ class RepeaterType extends FieldTypeBase
     {
         $key = $this->mapping['fieldname'];
         if ($this->isJson($data[$key])) {
-            $originalMapping[$key]['fields'] = $this->mapping['fields'];
+            $originalMapping[$key]['fields'] = $this->mapping['data']['fields'];
             $originalMapping[$key]['type'] = 'repeater';
             $mapping = $this->em->getMapper()->getRepeaterMapping($originalMapping);
Fix for Notice and subsequent warning related to repeater fields

Notice: Undefined index: fields in C:\MAMP\htdocs\nuffieldtrust.org.uk\vendor\bolt\bolt\src\Storage\Field\Type\RepeaterType.php on line <I>