diff --git a/app/Http/Controllers/InvoiceController.php b/app/Http/Controllers/InvoiceController.php
index e4dc4db7..e379fa8d 100644
--- a/app/Http/Controllers/InvoiceController.php
+++ b/app/Http/Controllers/InvoiceController.php
@@ -365,7 +365,7 @@ class InvoiceController extends Controller
             }
 
             $zip->close();
-            $attachment = base64_encode(File::get($zipname));
+            $attachment = chunk_split(base64_encode(File::get($zipname)));
 
             Mail::raw( 'DO for bookings po approved on '.Carbon::today(), function($message) use ($attachment){
                 $message->from('exchange@cief-malaysia.com');