Importing excel file, return Carbon problem

I am trying to import excel file, there is a column with "date" information, when I insert in to database it return like this that contains date field return "Cannot use object of type Carbon\Carbon as array"",

here is my controller codes:

public function importExcel(Request $request)
    {
        //$this->validate($request, [ 'excel' => 'required|mimes:xls,xlsx']); 
        if($request->hasFile('excel')){
        $path = $request->file('excel')->getRealPath();
        $data = Excel::load($path, function($reader) {})->get();
            if(!empty($data) && $data->count()){
                foreach ($data->toArray() as $key => $rows) {
                    if(!empty($rows)){
                        foreach ($rows as $row) {        
                            $insert[] = [
                                    'tanggal' => $row['tanggal'],
                                    'waktu' => $row['waktu'],
                                    'lintang' => $row['lintang'],
                                    'bujur' => $row['bujur'],
                                    'magnitudo' => $row['magnitudo'],
                                    'kedalaman' => $row['kedalaman'],
                                    'lokasi' => $row['lokasi'],
                                    'terasa' => $row['terasa'],
                                    'dirasakan' => $row['dirasakan'],
                                    'pga_z' => $row['pga_z'],
                                    'pga_ns' => $row['pga_ns'],
                                    'pga_ew' => $row['pga_ew'],
                                    'sumber' => $row['sumber']
                            ];

                        }
                    }
                }
                if(!empty($insert)){
                        Gempabumi::insert($insert);
                        \Alert::success('Data berhasil ditambahkan')->flash();
                    return redirect('admin/pengamatan/gempabumi');
                }
            }
        }
        //\Alert::error('Ada yang salah dengan data anda, tolong perbaiki')->flash();
        return back()->with('error', 'Ada yang salah, silahkan cek data anda');
    }

and here is the error

[2017-02-02 22:14:27] local.ERROR: Symfony\Component\Debug\Exception\FatalThrowableError: Cannot use object of type Carbon\Carbon as array in /Users/jambari/Desktop/code/office/app/Http/Controllers/MagnetbumiController.php:155

How to fix this ? please help me !