RadComboBox with ItemTemplate and FooterTemplate UI issue

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:telerik="http://schemas.telerik.com/2022/xaml/maui"
             x:Class="TestRadComboBox.MainPage">
    <ScrollView>
        <VerticalStackLayout
            Spacing="25"
            Padding="30,0"
            VerticalOptions="Center">
            <telerik:RadComboBox ItemsSource="{Binding Items}" 
                                 DisplayMemberPath="Name"
                                 IsEditable="True"
                                 SearchMode="Contains"
                                 SearchTextPath="Name"
                                 Placeholder="Select which city you want to visit"
                                 SelectionMode="Multiple"
                                 DropDownHeight="300"
                                 x:Name="comboBox">
                <telerik:RadComboBox.FooterTemplate>
                    <DataTemplate>
                        <StackLayout>
                            <Button Text="Add Items" 
                                    BackgroundColor="LightBlue"/>
                        </StackLayout>
                    </DataTemplate>
                </telerik:RadComboBox.FooterTemplate>
                <telerik:RadComboBox.ItemTemplate>
                    <DataTemplate>
                        <Label Text="{Binding Name}" TextColor="Black"/>
                    </DataTemplate>
                </telerik:RadComboBox.ItemTemplate>
            </telerik:RadComboBox>
        </VerticalStackLayout>
    </ScrollView>
</ContentPage>

namespace TestRadComboBox;

public partial class MainPage : ContentPage
{
	public MainPage()
	{
		InitializeComponent();
		BindingContext = new ViewModel();
	}
}

namespace TestRadComboBox
{
    public class City
    {
        public string Name { get; set; }
        public int Population { get; set; }
    }
}

using System.Collections.ObjectModel;

namespace TestRadComboBox
{
    public class ViewModel
    {
        public ViewModel()
        {
            this.Items = new ObservableCollection<City>
            {
                new City { Name = "Tokyo", Population = 13929286 },
                new City { Name = "New York", Population = 8623000 },
                new City { Name = "London", Population = 8908081 },
                new City { Name = "Madrid", Population = 3223334 },
                new City { Name = "Los Angeles", Population = 4000000},
                new City { Name = "Paris", Population = 2141000 },
                new City { Name = "Beijing", Population = 21540000 },
                new City { Name = "Singapore", Population = 5612000 },
                new City { Name = "New Delhi", Population = 18980000 },
                new City { Name = "Bangkok", Population = 8305218 },
                new City { Name = "Berlin", Population = 3748000 },
                new City { Name = "Tokyo", Population = 13929286 },
                new City { Name = "New York", Population = 8623000 },
                new City { Name = "London", Population = 8908081 },
                new City { Name = "Madrid", Population = 3223334 },
                new City { Name = "Los Angeles", Population = 4000000},
                new City { Name = "Paris", Population = 2141000 },
                new City { Name = "Beijing", Population = 21540000 },
                new City { Name = "Singapore", Population = 5612000 },
                new City { Name = "New Delhi", Population = 18980000 },
                new City { Name = "Bangkok", Population = 8305218 },
                new City { Name = "Berlin", Population = 3748000 },
                new City { Name = "Tokyo", Population = 13929286 },
                new City { Name = "New York", Population = 8623000 },
                new City { Name = "London", Population = 8908081 },
                new City { Name = "Madrid", Population = 3223334 },
                new City { Name = "Los Angeles", Population = 4000000},
                new City { Name = "Paris", Population = 2141000 },
                new City { Name = "Beijing", Population = 21540000 },
                new City { Name = "Singapore", Population = 5612000 },
                new City { Name = "New Delhi", Population = 18980000 },
                new City { Name = "Bangkok", Population = 8305218 },
                new City { Name = "Berlin", Population = 3748000 },
            };
        }

        public ObservableCollection<City> Items { get; set; }
    }
}