composer require phpoffice/phpexcel

extend/service/PHPExcelService.php

@@ -87,6 +87,7 @@ class PHPExcelService
      */
     public function setExcelContent($list=null)
     {
+        self::$PHPExcel = new \PHPExcel();
         $sheet=self::$PHPExcel->getActiveSheet();
         foreach(self::$data as $key=>$val){
             $row=self::$cellKey[$key];

vendor/PHPExcel

@@ -1 +0,0 @@
-Subproject commit c269793ee715fb5a15f0b2ad25c064d9ee6e8e53