return response()->download(storage_path('app/files/gggusers.xlsx')); show's blank page

I have this code

return response()->download(storage_path('app/files/gggusers.xlsx'));

in my controller. It executes without any problem but instead of triggering the browser to download the excel file, it just displays a blank white page. I'm positive the file name & location is correct, because if I just change the file name gggusers.xlsx to something else or I delete the file, Laravel will display this error

The file "D:\web\speak\storage\app/files/gggusers.xlsx" does not exist.

via Chebli Mohamed