Attempted to load class "Spreadsheet" from namespace "PhpOffice\PhpSpreadsheet" - Symnfony4

Question

I have already imported PhpSpreadSheet in my controller.

I do this for calling the lib :

The libs is present in my vendor folder. (PHP 7.3)

Why I have the error below ??

"Attempted to load class "Spreadsheet" from namespace "PhpOffice\PhpSpreadsheet".↵Did you forget a "use" statement for another namespace"

Thanks

Answer 1

I update symfony flex and it's work. Thanks for you help.