diff --git a/src/BluescaleMailApi.php b/src/BluescaleMailApi.php
index 39bbd98..9be90ed 100644
--- a/src/BluescaleMailApi.php
+++ b/src/BluescaleMailApi.php
@@ -59,7 +59,7 @@ class BluescaleMailApi
                     $formatted_attachmments[] = $file;
                 }
 
-                $template->attachments($formatted_attachmments);
+                $template->attachments = $formatted_attachmments;
             }
         }