Update Cart Laravel

public function update(Request $request)
    {
        $price_product      = $request->price_product;
        $qty_cart           = $request->qty_cart;
        $price_cart         = $qty_cart * $price_product;

        foreach ($request->cart_id as $d => $cartId) {
            $data = Cart::where('cart_id', $cartId)->update([
                'qty_cart'      => $request->qty_cart,
                'price_cart'    => $price_cart,

            ]);

        }

        return redirect()->back();
    }

@extends('layouts.users.index')

@section('content')
<!-- Title Page -->
@if ($message = Session::get('success'))
<div class="alert alert-success alert-block">
    <button type="button" class="close" data-dismiss="alert">×</button>
    <strong>{{ $message }}</strong>
</div>
@endif

<section class="bg-title-page p-t-40 p-b-50 flex-col-c-m" style="background-image: url({{ asset('assets_front/images/food.jpg')}} );">
    <h2 class="l-text2 t-center">
        Cart
    </h2>
</section>

<!-- Cart -->
<section class="cart bgwhite p-t-70 p-b-100">
    <div class="container">
        <form id="" action="/update-cart" method="post" enctype="multipart/form-data">
            {{ csrf_field() }}
            <!-- Cart item -->
            <div class="container-table-cart pos-relative">
                <div class="wrap-table-shopping-cart bgwhite">
                    <table class="table-shopping-cart">
                        <tr class="table-head" style="background-color: #f59000;">
                            <th class="column-1"></th>
                            <th class="column-2">Product</th>
                            <th class="column-3">Price</th>
                            <th class="column-4">Quantity</th>
                            <th class="column-5">Total</th>
                        </tr>

                        @foreach($cart_header as $d)
                        @if($d->publication_status_cart == 0)
                        <?php
                        $customer_id = Auth::user()->id;
                        ?>
                        @if($d->customer_id == $customer_id)
                        <input type="hidden" id="" name="cart_id[]" value="{{ $d->cart_id }}" required="required" class="form-control col-md-7 col-xs-12">
                        <input type="hidden" id="" name="price_product" value="{{ $d->price_product }}" required="required" class="form-control col-md-7 col-xs-12">
                        <tr class="table-row">
                            <td class="column-1">
                                <div class="cart-img-product b-rad-4 o-f-hidden">
                                    <img src="{{ asset('assets/image_products/'.$d->image_product) }}" alt="IMG-PRODUCT">
                                </div>
                            </td>
                            <td class="column-2">{{ $d->name_product}}</td>
                            <td class="column-3">Rp.{{number_format($d->price_product,0)}}</td>
                            <td class="column-4">
                                <div class="flex-w bo5 of-hidden w-size17">
                                    <button type="submit" class="btn-num-product-down color1 flex-c-m size7 bg8 eff2">
                                        <i class="fs-12 fa fa-minus" aria-hidden="true"></i>
                                    </button>
                                    <input class="size8 m-text18 t-center num-product" type="number" name="qty_cart[]" value="{{ $d->qty_cart }}">

                                    <button type="submit" class="btn-num-product-up color1 flex-c-m size7 bg8 eff2">
                                        <i class="fs-12 fa fa-plus" aria-hidden="true"></i>
                                    </button>
                                </div>
                            </td>
                            <td class="column-5">Rp.{{number_format($d->price_cart,0)}}</td>
                        </tr>
                        @endif
                        @endif
                        @endforeach
                    </table>
                </div>
            </div>

            <div class="flex-w flex-sb-m p-t-25 p-b-25 bo8 p-l-35 p-r-60 p-lr-15-sm">
                <div class="flex-w flex-m w-full-sm">

                </div>

                <div class="size10 trans-0-4 m-t-10 m-b-10">
                    <!-- Button -->
                    <button class="flex-c-m sizefull bg1 bo-rad-23 hov1 s-text1 trans-0-4">
                        Update Cart
                    </button>
                </div>
            </div>
        </form>

        <!-- Total -->
    </div>
</section>
@endsection