上传文件报错 只有 Excel 多工作表时才报错 其他没问题

上传.xls文件时，单个工作表没问题，如果含有多个工作表报错

上传代码为简单的 $path = $request->file('files')->store('files');

请教如何解决
以下是报错提示

(1/1) ErrorException
fopen(D:\xampp\htdocs\newhr\public\uploads\files/Kcswsx62v6x11wHfasg8EIqIhFFusn3YqBHhkh9G.): failed to open stream: Permission denied

in Local.php (line 151)
at HandleExceptions->handleError(2, 'fopen(D:\xampp\htdocs\newhr\public\uploads\files/Kcswsx62v6x11wHfasg8EIqIhFFusn3YqBHhkh9G.): failed to open stream: Permission denied', 'D:\xampp\htdocs\newhr\vendor\league\flysystem\src\Adapter\Local.php', 151, array('path' => 'files/Kcswsx62v6x11wHfasg8EIqIhFFusn3YqBHhkh9G.', 'resource' => resource, 'config' => object(Config), 'location' => 'D:\xampp\htdocs\newhr\public\uploads\files/Kcswsx62v6x11wHfasg8EIqIhFFusn3YqBHhkh9G.'))
at fopen('D:\xampp\htdocs\newhr\public\uploads\files/Kcswsx62v6x11wHfasg8EIqIhFFusn3YqBHhkh9G.', 'w+b')