diff --git a/src/EventSubscriber/BillEventSubscriber.php b/src/EventSubscriber/BillEventSubscriber.php
index aef9f06..a2eb648 100644
--- a/src/EventSubscriber/BillEventSubscriber.php
+++ b/src/EventSubscriber/BillEventSubscriber.php
@@ -97,7 +97,7 @@ class BillEventSubscriber extends EntityManagerEventSubscriber
 
         $datas[] = $entity->getId().'.'.$splInfo->getExtension();
 
-        $expectedFilename = implode('_', $datas);
+        $expectedFilename = str_replace('/', '-', implode('_', $datas));
         $expectedPath = dirname($entity->getFile()).'/'.$expectedFilename;
 
         if ($splInfo->getFilename() !== $expectedFilename) {