no user matches the given query

hi everyone i am building a ecommerce webapp where everything is done except this. i want the user to get the product that it posted by itself my views.py file is:

class UserPostListView(ListView):
    model = Product
    template_name = 'product/user-posts.html'

    def get_queryset(self):
        user = get_object_or_404(User, email=self.kwargs.get('email'))
        return Product.objects.filter(author=user , is_staff=True).order_by('-date_posted')

my urls.py file is:

urlpatterns = [
   # path('featured/' , ProductFeaturedListView.as_view()),
    #path('featured/<int:pk>' , ProductFeaturedDetailView.as_view()),
    path('' , ProductListView.as_view(), name= "list"),
    path('new/' , ProductCreateView.as_view() , name="product-create"),
    path('<slug:slug>/update/' , ProductUpdateView.as_view() , name="product-update"),
    path('<slug:slug>/delete/' , ProductDeleteView.as_view() , name="product-delete"),
    #path('product-fbv/' , product_list_view),
    #path('product/<int:pk>' , ProductDetailView.as_view()),
    path('<slug:slug>/comment' , CommentCreateView.as_view() , name="add-comment"),
    path('<slug:slug>' , ProductDetailSlugView.as_view() , name="detail"),
    path('userpost/', UserPostListView.as_view(), name='user-post'),

   # path('product-fbv/<int:pk>' , product_detail_view),

]

and my user model is:

class User(AbstractBaseUser):
    email = models.EmailField(max_length=255 ,unique=True)
    full_name = models.CharField(max_length=255, blank=True, null=True)
    active = models.BooleanField(default=True)  #can login
    staff = models.BooleanField(default=False)  #staff user non super user
    admin = models.BooleanField(default=False)  #superuser
    time_stamp = models.DateTimeField(auto_now_add=True)

and my product models.py is:

class Product(models.Model):
    title = models.CharField(max_length=110)
    slug = models.SlugField(blank=True, unique=True)
    status = models.CharField(choices=CATEGORY_CHOICES, max_length=10)
    price = models.DecimalField(decimal_places=2, max_digits=6)
    discount_price=models.FloatField(blank=True, null=True)
    size = models.CharField(choices=SIZE_CHOICES, max_length=20)
    color = models.CharField(max_length=20, blank=True, null=True)
    image = models.ImageField(upload_to=upload_image_path)
    description = RichTextField(max_length=1000)
    featured = models.BooleanField(default=False)
    author = models.ForeignKey(User, on_delete=models.CASCADE)
    time_stamp = models.DateTimeField(auto_now_add=True)

and it give me the error that no user matches the given query