diff --git a/app/src/Model/Table/MatchgridsTable.php b/app/src/Model/Table/MatchgridsTable.php
index 463ab52ab..647850f8c 100644
--- a/app/src/Model/Table/MatchgridsTable.php
+++ b/app/src/Model/Table/MatchgridsTable.php
@@ -218,7 +218,7 @@ public function validationDefault(Validator $validator) {
       'content',
       [ 'rule' => [ 'maxLength', 32 ] ]
     );
-    $validator->allowEmpty('referenceid_start');
+    $validator->allowEmpty('referenceid_prefix');
     
     return $validator; 
   }