PopToRootAsync iOS error

Hi! I'm trying to close two windows in the same instruction. In Android PopToRootAsync works perfectly, but in iOS the app crashes.

The error says:

System.ArgumentNullException: Argument cannot be null.Parameter name: gestureRecognizer

My code:

public async void SaveButton()
{
    SaveData();
    await this.Navigation.PopToRootAsync();
}

I'm using Xlabs MVVM in Xamarin Forms. Any idea about the problem?