RelayCommand CanExecute doesn't work as expected.

[Wep4ik]

Hello. Could not make command work properly with CommandParameter.
Xaml:
<TextBox Name="TxtInput" Grid.Row="0" /> <Button Grid.Row="1" Content="Click me" Command="{Binding DoSomethingCommand}" CommandParameter="{Binding Text, ElementName=TxtInput}" />
Code
[RelayCommand(CanExecute = nameof(CanDoSomething))] private void DoSomething(string te) { } private bool CanDoSomething(string te) => !string.IsNullOrWhiteSpace(te);

When I type in TextBox I expect to fire CanDoSomething and enable button, but button is fired once on start and after is not notified.
Where is the problem?