Internal Server Error: MultiValueDictKeyError in Django

I have problem with my ecommerce project. When i try to add item to the cart I get this error. But item is in the cart and I get this problem only in my console. Can you please help me get rid of this error?

html code - https://i.sstatic.net/LCns9.png

{% for p in products %}
                        <div class="bg-white h-[400] w-[400]">

                            <div class=" flex bg-color1 text-sm text-white absolute p-2 m-4 rounded-full ">New</div>
                            <img class="w-4/5 flex mx-auto mt-2" src={{ p.image.url }} alt="">
                            <p class=" my-2 text-center text-sm">{{ p.category }}</p>
                            <a href={% url 'core:product-detail' p.pid %} class="my-2 flex items-center justify-center text-color1 font-medium text-xl">{{ p.title }}</a>

                            <div class="flex justify-center text-center mb-2">
                                <span class="shop__price">{{ p.price }} Kč</span>
                                <span class="text-sm line-through font-sm ml-2 text-color2">29.99 Kč</span>
                            </div>
                            <div class="add-cart flex justify-center text-center mb-2 ">
                                <input type="hidden" value="{{ p.id }}" class="product-id-{{ p.id }}">
                                <input type="hidden" value="{{ p.title }}" class="product-title-{{ p.id }}">
                                <input type="hidden" value="{{ p.image.url }}" class="product-image-{{ p.id }}">
                                <input type="hidden" value="{{ p.price }}" class="product-price-{{ p.id }}">
                                <input type="hidden" value="{{ p.pid }}" class="product-pid-{{ p.id }}">
                                <input type="hidden" value="1" class="product-qt-{{ p.id }}">

                                <button class="add-to-cart-btn flex justify-center text-center mb-2" data-index="{{ p.id }}">
                                    <a type="submit" id="add_to_cart" class="pointer inline-block bg-color1 text-white px-3 py-2 rounded-md font-medium transition hover:bg-color2 button">Add To Cart</a>
                                </button>
                            </div>
                            </div>
                        {% endfor %}

js code - https://i.sstatic.net/6NE7L.png

$("#add_to_cart, .add-to-cart-btn").on("click", function(){
  let this_val = $(this)
  let index = this_val.attr('data-index')
  let product_qt = $(".product-qt-" + index).val()
  let product_title = $(".product-title-" + index).val()
  let product_id = $(".product-id-" + index).val()
  let product_price = $(".product-price-" + index).val()
  let product_image = $(".product-image-" + index).val()
  let product_pid = $(".product-pid-" + index).val()
  
   $.ajax({
    url: '/add-to-cart',
    data: {
      'id': product_id,
      'pid': product_pid,
      'qt' : product_qt,
      'title' : product_title,
      'price' : product_price,
      'image' : product_image,
    },
    dataType: 'json',
    beforeSend: function(){
      console.log("addind the product")
    },
    success:function(response){
      console.log("product added")
      $(".cart-items-count").text(response.totalcartitems) 
    }
  })
})

view / function - https://i.sstatic.net/mja5v.png

def add_to_cart(request):
    cart_product = {}

    cart_product[str(request.GET["id"])] = {
        'title':request.GET['title'],
        'qt':request.GET['qt'],
        'price':request.GET['price'],
        'image':request.GET['image'],
        'pid':request.GET['pid'],
    }

    if 'cart_data_obj' in request.session:
        if str(request.GET["id"]) in request.session['cart_data_obj']:

            cart_data = request.session['cart_data_obj']
            cart_data[str(request.GET['id'])]['qt'] = int(cart_product[str(request.GET["id"])]['qt'])
            cart_data.update(cart_data)
            request.session['cart_data_obj'] = cart_data
        else:
            cart_data = request.session['cart_data_obj']
            cart_data.update(cart_product)
            request.session['cart_data_obj'] = cart_data
    else:
        request.session['cart_data_obj'] = cart_product

    return JsonResponse({"data":request.session['cart_data_obj'], 'totalcartitems': len(request.session['cart_data_obj']) }) 

VScode/ console - https://i.sstatic.net/aufFg.png

browser/ console - https://i.sstatic.net/hcwMm.png

error detail - https://i.sstatic.net/gEV1Y.png