original.cs

var orderRequest = await _orderRepository.GetItemAsync(id);

orderRequest.Approve();

await _orderRepository.UpdateItemAsync(orderRequest);

foreach (var lineItem in orderRequest.Items)  
{
    var stock = (await _stockRepository
        .GetItemsAsync(s => s.ProductId == lineItem.ProductId))
        .Single();

    stock.QuantityAvailable -= lineItem.Quantity;

    await _stockRepository.UpdateItemAsync(stock);
}

_client.Publish(new OrderApproved { OrderId = orderRequest.Id });