Popup does not appear in my App

Use Rg.Popup.Plugins to create popups. Well, when I put in design does not rotate, the screen dims, but I click on it and nothing happens. I put a button with red background and even then, it does not appear. I did a separate project and it works. In my project I use Syncfusion (Datagrid and Chart), I use the FirebasePushNotification plugin, the difference ~ for the other project. I thought something like that might be killing my Popup. See below the code used. XAML

<?xml version="1.0" encoding="utf-8" ?>
<pages:PopupPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:pages="clr-namespace:Rg.Plugins.Popup.Pages;assembly=Rg.Plugins.Popup"
             xmlns:animations="clr-namespace:Rg.Plugins.Popup.Animations;assembly=Rg.Plugins.Popup"
             x:Class="Autorizador.AprovarPopup">
    <!--Animations use example-->
    <StackLayout>
        <Label Text="Testando" BackgroundColor="Black" TextColor="Yellow"></Label>
    </StackLayout>
    <!--<pages:PopupPage.Animation>
        <animations:ScaleAnimation 
      PositionIn="Center"
      PositionOut="Center"      
      ScaleIn="1.2"
      ScaleOut="0.8"
      DurationIn="400"
      DurationOut="300"
      EasingIn="SinOut"
      EasingOut="SinIn"
      HasBackgroundAnimation="True"/>
    </pages:PopupPage.Animation>-->
    <StackLayout VerticalOptions="End" HorizontalOptions="Fill">
        <Button Margin="20,0,20,20" HeightRequest="80" Text="Fechar" Clicked="Fechar_OnClicked" BackgroundColor="Red"></Button>
    </StackLayout>
</pages:PopupPage>

My .cs

using Rg.Plugins.Popup.Pages;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using Xamarin.Forms;
using Xamarin.Forms.Xaml;

using Rg.Plugins.Popup.Extensions;

namespace Autorizador
{
    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class AprovarPopup : PopupPage
    {
        private TaskCompletionSource<bool> taskCompletionSource;
        public Task PopupClosedTask { get { return taskCompletionSource.Task; } }
        public AprovarPopup()
        {
            InitializeComponent();
        }

        //protected override void OnAppearing()
        //{
        //    base.OnAppearing();
        //    taskCompletionSource = new TaskCompletionSource<bool>();
        //    Debug.WriteLine("I'm getting rendered");
        //}

        //protected override void OnDisappearing()
        //{
        //    base.OnDisappearing();
        //    taskCompletionSource.SetResult(true);
        //}

        //// Method for animation child in PopupPage
        //// Invoced after custom animation end
        //protected override Task OnAppearingAnimationEnd()
        //{
        //    return Content.FadeTo(0.5);
        //}

        //// Method for animation child in PopupPage
        //// Invoked before custom animation begin
        //protected override Task OnDisappearingAnimationBegin()
        //{
        //    return Content.FadeTo(1);
        //}

        //protected override bool OnBackButtonPressed()
        //{
        //    // Prevent hide popup
        //    //return base.OnBackButtonPressed();
        //    return true;
        //}

        //// Invoced when background is clicked
        //protected override bool OnBackgroundClicked()
        //{
        //    // Return default value - CloseWhenBackgroundIsClicked
        //    return base.OnBackgroundClicked();
        //}

        //private async void Fechar_OnClicked(object sender, EventArgs e)
        //{
        //    await base.Navigation.PopPopupAsync();
        //}
    }
}

Please note that some methods have been commented out, as I have done so to see whether or not some of these methods are available.

EDIT1

In this line public partial class AprovarPopup : PopupPage , when I click on F12 on PopupPage gives me this message:

  

Can not navigate to the symbol under the cursor

Can this be the problem that is happening, am I not inheriting anything or not?

What is appearing is that PopupPage is not being recognized and I do not know why.

EDIT2

I created another form with popup and it worked. That was the answer. Post closed, thank you.