Xamarin Forms Plugin.BLE Can't find any devices

I wanted to write a simple application that sends bits to a bluetooth device. Currently I don't know what is wrong and I don't know where I got the bug. I've got all permissions and i am asking for them (only localization showing up on screen)

    <uses-permission android:name="android.permission.BLUETOOTH" />
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

I am using Plugin.BLE NuGet package. The StateChangedEvent works just fine. However when I scan no devices are found (even though I have devices available for discovery).

  public partial class MainPage : ContentPage
    {
        IBluetoothLE ble;
        IAdapter adapter;
        ...
    }
    public MainPage()
        {
            InitializeComponent();
            ble = CrossBluetoothLE.Current;
            adapter = CrossBluetoothLE.Current.Adapter;
            Devices = new ObservableCollection<Device_bluetooth>();
            ble.StateChanged += (s, e) =>
            {
                labelTest.Text=($"The bluetooth state changed to {e.NewState}");
                DisplayAlert("Notice", e.NewState.ToString(), "OK !");
            };
        }

The function for scanning to discover devices below:

// Issue is here
        private async void ScanAsync()
        {
            try
            {
                Devices.Clear();
                adapter.DeviceDiscovered += (s, a) =>
                {
                    Devices.Add(new Device_bluetooth() { Device = a.Device, Name = "Name: " + a.Device.Name.ToString(), Uuid = "UUID:" + a.Device.Id.ToString() });
                };

                if (!ble.Adapter.IsScanning)
                {
                    await adapter.StartScanningForDevicesAsync();
                }
            }
            catch (Exception ex)
            {
                await DisplayAlert("Notice", ex.Message.ToString(), "Error !");
            }

Device_bluetooth is my class for for storing devices, and I am showing them in a ListView like below:

        <ListView x:Name="mylistview" ItemsSource="{Binding Devices}" HasUnevenRows="True">
            <ListView.ItemTemplate>
                <DataTemplate>
                    <ViewCell Height="100">
                        <StackLayout>
                            <Frame  BackgroundColor="White"
                              HasShadow="true">
                                <StackLayout HeightRequest="100">
                                    <Label Text="{Binding Name ,Mode=TwoWay}"   />
                                    <Label Text="{Binding Uuid ,Mode=TwoWay}"   />
                                </StackLayout>
                            </Frame>
                        </StackLayout>
                    </ViewCell>
                </DataTemplate>

            </ListView.ItemTemplate>
        </ListView>

Please help. I have tried almost everything and I cannot cope with it.