ScrollView does't scroll to the end

Hello to you! I have a problem which I can not find a solution. I have a scroll view that blocks scroll up to about half of the page. I Post my XAML to give a better idea:

< ?xml version="1.0" encoding="UTF-8"?>
< ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="Myapp.Dettail"
BackgroundImage="bgSmart.jpg"
Title="My Page">
< ContentPage.Content>
< ScrollView VerticalOptions="Fill" HorizontalOptions="StartAndExpand">
< StackLayout Orientation="Vertical" HorizontalOptions="CenterAndExpand" VerticalOptions="StartAndExpand">
< Grid x:Name="Grid1" RowSpacing="0">
< Grid.RowDefinitions>
< RowDefinition Height="80" />
< RowDefinition Height="" />
< RowDefinition Height="25" />
< RowDefinition Height="35" />
< RowDefinition Height="25" />
< RowDefinition Height="35" />
< RowDefinition Height="35" />
< RowDefinition Height="35" />
< RowDefinition Height="25" />
< RowDefinition Height="35" />
< RowDefinition Height="" />
< /Grid.RowDefinitions>
< Label x:Name="titleLabel" Grid.Row="0" TextColor="#00c3b2" FontSize="30" FontAttributes="Bold" />
< Label x:Name="infoLabel" Grid.Row="1" VerticalTextAlignment="Start" />
< Label Text="Some Text" Grid.Row="2" Style="{StaticResource sezioneLabelStyle}" />
< Label x:Name="presidentLabel" Grid.Row="3" />
< Label Text="Contacts" Grid.Row="4" Style="{StaticResource sezioneLabelStyle}" />
< Label x:Name="streetLabel" Grid.Row="5" />
< Label x:Name="telephoneLabel" Grid.Row="6" />
< Label x:Name="faxLabel" Grid.Row="7" />
< Label x:Name="emailLabel" Grid.Row="8" />
< Label x:Name="infoContactLabel" Grid.Row="9" VerticalTextAlignment="Start" />
< /Grid>
< ListView x:Name="officeListiView" RowHeight="215">
< ListView.ItemTemplate>
< DataTemplate>
< ViewCell>
< ViewCell.View>
< Grid RowSpacing="0">
< Grid.RowDefinitions>
< RowDefinition Height="25" />
< RowDefinition Height="35" />
< RowDefinition Height="35" />
< RowDefinition Height="35" />
< RowDefinition Height="35" />
< RowDefinition Height="*" />
< /Grid.RowDefinitions>
< Label Grid.Row="0" Text="{Binding OfficeName}" Style="{StaticResource sezioneLabelStyle}" />
< Label Grid.Row="1" Text="{Binding Contact.Place}" />
< Label Grid.Row="2" Text="{Binding Contact.CellTelephone}" />
< Label Grid.Row="3" Text="{Binding Contact.CellFax}" />
< Label Grid.Row="4" Text="{Binding Contact.CellEmail}" />
< Label Grid.Row="5" Text="{Binding Contact.Info}" VerticalTextAlignment="Start" />
< /Grid>
< /ViewCell.View>
< /ViewCell>
< /DataTemplate>
< /ListView.ItemTemplate>
< /ListView>
< /StackLayout>
< /ScrollView>
< /ContentPage.Content>
< /ContentPage>

Once you visualize the page if there is Grid1 the scrollView is not be able to show all the data within OfficeListView

Instead if I comment Grid1 then the listview comes down to OfficeView.

I hope I was clear why a hand would make me really comfortable!
Thank you in advance