Append to existing file ERROR: Illegal offset type in isset or empty

[edward-buskus]

I need open existing xls file and append new sheet.

 Excel::load('/public/template.xlsx', function($reader)  {
            $reader->sheet(function($sheet)
            {
                $sheet->appendRow([
                    'test1', 'test2',
                ]);
            });
        })->export('xlsx');

But i get error : ErrorException in PHPExcel.php line 575: Illegal offset type in isset or empty
If i set some sheet name

 Excel::load('/public/storistemplate.xlsx', function($reader)  {
            $reader->sheet('NewSheet',function($sheet)
            {
                $sheet->appendRow([
                    'test1', 'test2',
                ]);
            });
        })->export('xlsx');

I get error : FatalErrorException in HomeController.php line 234: Call to a member function appendRow() on a non-object

[patrickbrouwers]

Appending new sheets to a template is not yet supported.