Laravel Create Products Orders for each Shop in Api

I'm building a JSON Restful API for the eCommerce app

I have the following tables

Orders:

Schema::create('orders', function (Blueprint $table) {
        $table->id();
        $table->string('order_number');
        $table->unsignedBigInteger('user_id');
        $table->enum('status', ['pending','processing','completed','decline'])->default('pending');
        $table->float('grand_total');
        $table->integer('item_count');
        $table->boolean('is_paid')->default(false);
        $table->enum('payment_method', ['cash_on_delivery'])->default('cash_on_delivery');
        $table->string('notes')->nullable();

        $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
        $table->timestamps();
    });

Order Items

Schema::create('order_items', function (Blueprint $table) {
        $table->id();
        $table->unsignedBigInteger('order_id');
        $table->unsignedBigInteger('product_id');

        $table->foreign('product_id')->references('id')->on('products')->onDelete('cascade');
        $table->foreign('order_id')->references('id')->on('orders')->onDelete('cascade');

        $table->float('price');
        $table->integer('quantity');

        $table->timestamps();
    });

Products

Schema::create('products', function (Blueprint $table) {
        $table->id();
        $table->string('name');
        $table->date('expire_date');
        $table->decimal('price');
        $table->string('cover_img')->nullable();
        $table->unsignedBigInteger('shop_id')->nullable();
        $table->foreign('shop_id')->references('id')->on('shops')->onDelete('cascade');
        $table->timestamps();
    });

Shops

Schema::create('shops', function (Blueprint $table) {
        $table->id();
        $table->string('name');
        $table->integer('phone');
        $table->string('address');
        $table->boolean('status')->default(false);
        $table->unsignedBigInteger('user_id')->nullable();
        $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');

        $table->timestamps();
    });

Now, I can create an order with items successfully but what I wanna do is to make a single order for each shop

for example:

if user select products from 3 different Shops

instead of creating 1 orders with these products,

I wanna create 3 orders. one for each shop.

Controller

function store(Request $request)
{

    DB::beginTransaction();
    try{

        $order = new Order();
        $order->order_number = uniqid('ORD.');
        $order->user_id = Auth::id();
        $order->item_count = 2;
        $order->grand_total = 20;
        $order->save();

        $items = json_decode($request->getContent(), true);

        foreach( $items as $item ){
            $orderItem = new OrderItem;
            $orderItem->order_id = $order->id;
            $orderItem->product_id = $item['product_id'];
            $orderItem->price = $item['price'];
            $orderItem->quantity = $item['quantity'];
            $orderItem->save();
        }
      DB::commit();
    }catch (\Exception $e ){
        DB::rollBack();
    }
    return response(['message'=>'successful']);
}

Example of the JSON Post Request in Postman

[
                    {
                     "product_id":6,
                     "Shop_id"
                     "price":10,
                     "quantity":7
                    },
                    {
                     "product_id":10,
                     "Shop_id"
                     "price":14,
                     "quantity":2
                    },
                    {
                     "product_id":5,
                     "Shop_id"
                     "price":18,
                     "quantity":5
                    }
                ]

any ideas to do this?

NOTE

I made "item_count" and "grand_total" as a static data for now just for test