Importing firebase data into the Special Date parameter

[developersimsek]

Hello there,
I'm sorry, I've looked at open issues, but I can't find a solution to my problem.
What I want to do; Importing the dates in the firebase database to SpecialDates. I successfully retrieve data from Firebase, but I cannot import it to the calendar. I tried this with the following method, but I didn't succeed. I would be glad if you help. Thanks in advance ...

Xaml source

<controls:Calendar
Padding="10,0,10,0"
SelectedBorderWidth="4"
DisabledBorderColor="Black"
ShowNumberOfWeek="false"
StartDay="Monday"
TitleLabelTextColor="Purple"
DateClicked="Calendar_DateClicked"
x:Name="calender"
BindingContext="{Binding Tarih}"
WeekdaysShow="True"
WeekdaysFontAttributes="Bold"
EnableTitleMonthYearView="True"
TitleLeftArrowTextColor="Blue"
SelectedDate="{Binding Date}"
SpecialDates="{Binding Tarih}"

		DateCommand="{Binding DateChosen}" >

                </controls:Calendar>

Cs Source
public Detail()
{
InitializeComponent();
DBFire data;
data = new DBFire();
Device.BeginInvokeOnMainThread(async () =>
{
calender.BindingContext = await data.GetList();

        }
     );
    }