uwp twoway binding not updating UI - xaml

Question

I have the following XAML code, where I have a TextBox for user input (phone number) and GridView for user contacts.
<GridView x:Name="ContactsCollection" Grid.Row="1" Style="{StaticResource DefaultGridView}" IsItemClickEnabled="True" ItemsSource="{Binding UserContacts}" ItemTemplate="{StaticResource HorizontalGridViewDataTemplate}" ItemContainerStyle="{StaticResource DefaultGridViewItemContainer}">
<i:Interaction.Behaviors>
<c:EventTriggerBehavior EventName="SelectionChanged">
<c:InvokeCommandAction Command="{Binding SelectContactCommand}" CommandParameter="{Binding SelectedItem, ElementName=ContactsCollection}"/>
</c:EventTriggerBehavior>
</i:Interaction.Behaviors>
<GridView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</GridView.ItemsPanel>
And my TextBox that is binded to the Recipient in the ViewModel.
<TextBox x:Uid="Recipient" Text="{Binding Recipient, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" PreventKeyboardDisplayOnProgrammaticFocus="True" toolkitControls:TextBoxMask.Mask="7(999)999-99-99" toolkitControls:TextBoxMask.PlaceHolder="X" InputScope="NumericPin" HeaderTemplate="{StaticResource UiControlHeaderDataTemplate}" Style="{StaticResource DefaultTextBoxStyle}"/>
Here goes code from the ViewModel.
public string Recipient
{
get { return _recipient; }
set
{
if (value != _recipient)
{
_recipient = value;
RaisePropertyChanged(nameof(Recipient));
ContinueTransferCommand.RaiseCanExecuteChanged();
}
}
}
Now, when I click any contact from the GridView the following functions is called, that assign contact's phone number to the Recipient property.
private void SelectContactCommandAction(object contact)
{
Contact c = contact as Contact;
if (c.Phones?.Count > 0)
Recipient = FormatDataHelper.FormatPhoneNumber(c.Phones.FirstOrDefault().Number);
}
When I click any contact for the FIRST time, the Recipient property is updated, and the UI is updated too. But, if I select other contact, in the debug mode I can see, that Recipient property is updated and saved new value, but the UI (TextBox) is not updated at all. The only way it works, I have to delete any character from the TextBox and select a contact again, in that case UI value will be updated again.
Can somebody please explain this?