Undefined offset:1 Laravel import_excel

i need your help to solve my problem.

<?php

namespace App\Imports;

use App\Models\Produk;
use Maatwebsite\Excel\Concerns\ToModel;

class ProdukImport implements ToModel
{
    public function model(array $row)
    {
        return new Produk([
            'nama_produk'   => $row[0],
            'id_kategori'   => $row[1],
            'merk'          => $row[2],
            'harga_beli'    => $row[3],
            'code'          => $row[4],
            'harga_jual'    => $row[5],
            'stok'          => $row[6],
        ]);
    }

}

[this is my excel ][1] [1]: https://ift.tt/36MLHas

it keeps showing something wrong with 'id_kategori' i dont know how to solve this please i need your help