When having the android:supportsRtl="false" in the AndroidManifest file, the today and selected date text moves up
Solution:
set the property to true.
When setting height to the day name label style
<Style TargetType="Label" x:Key="DayNameLabelStyle">
<Setter Property="HeightRequest" Value="20" />
</Style>the day names (names of the week days) disappear