Remove item from cart (eCommerce)

Hi Good day Team,

I'm begginer and currently developing an eCommerce project.

I have found a tutorial on add/remove to cart from youtube. its works fine, but the problem i faced is, when completely remove / remove all the items from cart.

the cart value is become '0' and the iems is removed, means its working fine. but in Admin dashboard the Order Item and Order on the user is still there. 

Can guide on this issue?

Here is the code below:

Model.py

class Products(models.Model):

    productname = models.CharField(max_length=255, blank=True, null=True)  

    productprice = models.IntegerField(blank=True, null=True)

class OrderItem(models.Model):

    user = models.ForeignKey(User, on_delete=models.CASCADE)

    item = models.ForeignKey(Products, on_delete=models.CASCADE)

    quantity = models.IntegerField(default=1)

    ordered = models.BooleanField(default=False)

    def __str__(self):

        return f"{self.quantity} of {self.item.productname}"

    def get_total_item_price(self):

        return self.quantity * self.item.productprice

    def get_final_price(self):

        return self.get_total_item_price()

class Order(models.Model):

    user = models.ForeignKey(User, on_delete=models.CASCADE)

    ref_code = models.CharField(max_length=20, blank=True, null=True)

    ordered = models.BooleanField(default=False)

    items = models.ManyToManyField(OrderItem)

    start_date = models.DateTimeField(auto_now_add=True)

    ordered_date = models.DateTimeField()

    def __str__(self):

        return self.user.username

    def get_total(self):

        total = 0

        for order_item in self.items.all():

            total += order_item.get_final_price()

        return total

View.py

@login_required

def addtocart(request, Proid):

    #item = get_object_or_404(Products, id=id)

    item = Products.objects.get(id=Proid)

    order_item, created = OrderItem.objects.get_or_create(user=request.user, item=item, ordered=False)

    order_qs = Order.objects.filter(user=request.user, ordered=False)

    if order_qs.exists():

        order = order_qs[0]

        # check if the order item is in the order ==(order ache,for same-orderitem)

        if order.items.filter(item__id=item.id).exists():

            order_item.quantity += 1

            order_item.save()

            messages.info(request, "This product quantity was updated.")

            return redirect('ProductDetail')

        else:

            order.items.add(order_item)

            messages.info(request, "This product is added to your cart")

            return redirect('ProductDetail')

    else:

        ordered_date = timezone.now()

        order = Order.objects.create(user=request.user, ordered_date=ordered_date)

        order.items.add(order_item)

        messages.info(request, "This product is added to your cart")

        return redirect('ProductDetail')

@login_required

def removefromcartdetail(request, Proid):

    item = get_object_or_404(Products, id=Proid)

    order_qs = Order.objects.filter(

        user=request.user,

        ordered=False

    )

    if order_qs.exists():

        order = order_qs[0]

        # check if the order item is in the order

        if order.items.filter(item__id=item.id).exists():

            order_item = OrderItem.objects.filter(

                item=item,

                user=request.user,

                ordered=False

            )[0]

            order_item.quantity = 1

            order_item.save()

            order.items.remove(order_item)

            messages.info(request, "This item was removed from your cart.")

            return redirect('CartDetail')

        else:

            messages.info(request, "This item was not in your cart")

            return redirect('CartDetail')

    else:

        messages.info(request, "You do not have an active order")

        return redirect('CartDetail')