Update multiple row with insert new data in laravel

I am new to Laravel, here my existing fields are getting updated but unable to insert a new row, when users checks for a new category it should be added as a new row in the database.

public function update(Request $request, $id)
{
    $this->validate($request, [
        'name' => 'required',
        'shop_id' => 'required',
        'sub_category_id' => 'sometimes|required|',
        'is_visible' => 'required',
        'is_active' => 'required',
    ]);
    try {
         $product = Product::find($id);
         $product->name = $request->name;
         $product->shop_id = $request->shop_id;
         $product->is_visible = $request->is_visible;
         $product->is_active = $request->is_active;
         $product->save();



         foreach($request->category_id as $key =>$v){

            $data = array(

                'product_id'=>$id,
                'category_id'=> $v,
                'sub_category_id'=>isset($request->sub_category_id [$key])?$request->sub_category_id [$key]:null,
                'total_quantity'=>$request->total_quantity [$key],
                'quantity_unit'=>$request->quantity_unit [$key]
            );


            $ewast = EwasteItem::where('product_id','=',$id)->where('category_id','=',$request->category_id [$key])->get();

            if ($ewast) {
                $ewasteitem = EwasteItem::where('product_id',$id)->where('category_id',$v);
                $ewasteitem->update($data);
            } else {
                 EwasteItem::insert($data);
            }
        }
        return Redirect::route('ewaste.index')->with('successMessage', 'Product Updated Successfully.');
    } catch (ModelNotFoundException $e) {
        return $e;
    }
}

Answer

Update the foreach loop as follow

foreach($request->category_id as $key =>$v) {

    $data = array(

        'product_id'=>$id,
        'category_id'=> $v,
        'sub_category_id'=>isset($request->sub_category_id [$key])?$request->sub_category_id [$key]:null,
        'total_quantity'=>$request->total_quantity [$key],
        'quantity_unit'=>$request->quantity_unit [$key]
    );

    $ewasteitem = AppEwasteItem::updateOrCreate(
        ['product_id' => $id, 'category_id' => $v],
        $data
    );
}

also, check that in your AppEwasteItem model have $fillable array and it has the element ‘product_id’

protected $fillable = ['product_id', ...other_column_names];