public partial class MainPage : ContentPage
{
    public MainPage()
    {
        InitializeComponent();

        this.chart.HandlerChanged += this.Chart_HandlerChanged;
    }

    private void Chart_HandlerChanged(object sender, EventArgs e)
    {
        this.UpdateChart();
    }

    private void UpdateChart()
    {
        var platformView = this.chart.Handler.PlatformView;
#if IOS || MACCATALYST
        var platformChart = (Telerik.Maui.Controls.Compatibility.ChartRenderer.iOS.TKExtendedChart)platformView;
platformChart.YAxis.Style.LineHidden = false;
#endif
    }
}

<?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:telerikChart="clr-namespace:Telerik.XamarinForms.Chart;assembly=Telerik.Maui.Controls.Compatibility"
             x:Class="MauiApp1.MainPage">

    <telerikChart:RadCartesianChart MinimumHeightRequest="300">
        <telerikChart:RadCartesianChart.HorizontalAxis>
            <telerikChart:NumericalAxis LabelFitMode="MultiLine" />
        </telerikChart:RadCartesianChart.HorizontalAxis>
        <telerikChart:RadCartesianChart.VerticalAxis>
            <telerikChart:NumericalAxis />
        </telerikChart:RadCartesianChart.VerticalAxis>

        <telerikChart:RadCartesianChart.Series>
            <telerikChart:ScatterSplineSeries XValueBinding="NumericalData.XData" YValueBinding="NumericalData.YData" ItemsSource="{Binding Data1}" />
        </telerikChart:RadCartesianChart.Series>
    </telerikChart:RadCartesianChart>
</ContentPage>

namespace MauiApp1;

using System.Collections.ObjectModel;

public partial class MainPage : ContentPage
{
    public MainPage()
    {
        InitializeComponent();
        Data1 = GetNumericData1();
        BindingContext = this;
    }
    
    public ObservableCollection<Item> Data1 { get; set; }
    
    public static ObservableCollection<Item> GetNumericData1()
    {
        var data = new ObservableCollection<Item>
        {
            new Item { NumericalData = new NumericalData { XData = 2, YData = 13 } },
            new Item { NumericalData = new NumericalData { XData = 19, YData = 31 } },
            new Item { NumericalData = new NumericalData { XData = 22, YData = 33 } },
            new Item { NumericalData = new NumericalData { XData = 28, YData = 35 } },
            new Item { NumericalData = new NumericalData { XData = 33, YData = 46 } },
            new Item { NumericalData = new NumericalData { XData = 38, YData = 34 } },
            new Item { NumericalData = new NumericalData { XData = 49, YData = 66 } },
            new Item { NumericalData = new NumericalData { XData = 55, YData = 24 } },
            new Item { NumericalData = new NumericalData { XData = 62, YData = 41 } },
        };
        return data;
    }
}

public class NumericalData
{
    public double XData { get; set; }
    public double YData { get; set; }
}

public class Item
{
    public NumericalData NumericalData { get; set; }
}