x:Bind System.Runtime.InteropServices.COMException: „Unspecified error”

[mx2rel]

Hi, I've x:Bind with a custom control. Whenever I display the page (with the control), it crashes with the exception - System.Runtime.InteropServices.COMException: 'Unspecified error Cannot find a resource with the given key: BoolToVisibilityConverter.'

MessagesPage.xaml

<ListView ItemsSource="{x:Bind Received, Mode=OneWay}" IsItemClickEnabled="True" SelectionMode="None" Grid.Row="1" Margin="0,10,0,0" ItemClick="ListView_ItemClick">
            <ListView.ItemTemplate>
                <DataTemplate x:DataType="local:MessageViewModel">
                    <controls:SingleMessageBig Message="{Binding}"/>
                </DataTemplate>
            </ListView.ItemTemplate>
        </ListView>

SingleMessageBig.xaml

<UserControl
    x:Class="VulcanForWindows.UserControls.SingleMessageBig"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:VulcanForWindows.UserControls"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">

    <Grid DataContext="{x:Bind Message, Mode=OneWay}">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="30"/>
            <ColumnDefinition Width="250"/>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="auto"/>
        </Grid.ColumnDefinitions>
        <CheckBox IsChecked="{x:Bind Message.IsSelected, Mode=TwoWay}" VerticalAlignment="Center"/>
        <TextBlock Text="{x:Bind Message.message.Sender.Name, Mode=OneWay}"
                               TextWrapping="NoWrap" TextTrimming="CharacterEllipsis"
                               FontWeight="Medium" FontSize="16" VerticalAlignment="Center" Grid.Column="1"/>
        <Grid Grid.Column="2">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="auto"/>
                <ColumnDefinition Width="20"/>
                <ColumnDefinition Width="*"/>
            </Grid.ColumnDefinitions>
            <TextBlock Text="{x:Bind Message.message.Subject, Mode=OneWay}" VerticalAlignment="Center" FontWeight="Bold"/>
            <TextBlock Text="|" TextAlignment="Center" HorizontalAlignment="Center" VerticalAlignment="Center" Grid.Column="1"/>
            <TextBlock Text="{x:Bind Message.PlainContent, Mode=OneWay}" 
                                   VerticalAlignment="Center" Grid.Column="2"
                                   TextTrimming="CharacterEllipsis" />

        </Grid>
        <StackPanel Orientation="Horizontal" Grid.Column="3" Padding="10,0,0,0" Spacing="5">
            <TextBlock Text="{x:Bind Message.message.DateSent, Mode=OneWay}" HorizontalAlignment="Right" VerticalAlignment="Center"
                                       Visibility="{x:Bind Message.Hover, Mode=OneWay, Converter={StaticResource VisibilityConverter},ConverterParameter=True}"/>
            <Button HorizontalAlignment="Right" VerticalAlignment="Center"
                                       Visibility="{x:Bind Message.Hover, Mode=OneWay, 
                                    Converter={StaticResource VisibilityConverter},ConverterParameter=False}"
                                        Width="32" Height="32" Padding="0">
                <SymbolIcon Symbol="Delete" />
            </Button>
            <Button HorizontalAlignment="Right" VerticalAlignment="Center"
                                       Visibility="{x:Bind Message.Hover, Mode=OneWay, 
                                    Converter={StaticResource VisibilityConverter},ConverterParameter=False}"
                                        Width="32" Height="32" Padding="0">
                <SymbolIcon Symbol="Read" />
            </Button>
        </StackPanel>
    </Grid>
</UserControl>

SingleMessageBig.xaml.cs

using Microsoft.UI.Xaml;
using Microsoft.UI.Xaml.Controls;
using Microsoft.UI.Xaml.Controls.Primitives;
using Microsoft.UI.Xaml.Data;
using Microsoft.UI.Xaml.Input;
using Microsoft.UI.Xaml.Media;
using Microsoft.UI.Xaml.Navigation;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices.WindowsRuntime;
using Windows.Foundation;
using Windows.Foundation.Collections;

// To learn more about WinUI, the WinUI project structure,
// and more about our project templates, see: http://aka.ms/winui-project-info.

namespace VulcanForWindows.UserControls
{
    public sealed partial class SingleMessageBig : UserControl, INotifyPropertyChanged
    {

        public event PropertyChangedEventHandler PropertyChanged;
        public void OnPropertyChanged(string propertyName)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName)); //error there

        }

        public static readonly DependencyProperty MessageProperty =
            DependencyProperty.Register("Message", typeof(MessageViewModel), typeof(SingleMessageBig), new PropertyMetadata(null, Message_Changed));

        public MessageViewModel Message
        {
            get => (MessageViewModel)GetValue(MessageProperty);
            set => SetValue(MessageProperty, value); //error there
        }

        private static void Message_Changed(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            if (d is SingleMessageBig control && e.NewValue is MessageViewModel newValue)
            {
                control.OnPropertyChanged(nameof(Message)); //error there
            }
        }
        void HoverOn(object sender, PointerRoutedEventArgs e)
        {
            if (e.OriginalSource is FrameworkElement element)
            {
                // Access the data of the item being hovered
                MessageViewModel itemData = element.DataContext as MessageViewModel;

                // Now, you can use itemData to access properties or perform actions
                // For example, show additional information based on the data
                if (itemData != null)
                {
                    itemData.Hover = true;
                }
            }
        }
        void HoverOff(object sender, PointerRoutedEventArgs e)
        {
            if (e.OriginalSource is FrameworkElement element)
            {
                // Access the data of the item being hovered
                MessageViewModel itemData = element.DataContext as MessageViewModel;

                // Now, you can use itemData to access properties or perform actions
                // For example, show additional information based on the data
                if (itemData != null)
                {
                    itemData.Hover = true;
                }
            }
        }
        public SingleMessageBig()
        {
            OnPropertyChanged(nameof(Message));
            this.InitializeComponent();
            AddHandler(PointerEnteredEvent, new PointerEventHandler(HoverOn), true);
            AddHandler(PointerExitedEvent, new PointerEventHandler(HoverOff), true);
        }
    }
}

Couldn't find any way to fix it. Changing to Binding doesn't work. What's the issue?