IOS - ScrollView doesnt work on device

Hello,
I got the following Problem - Currently I am trying to output a Datagrid (Zumero) in a Stacklayout located in a ScrollView.

<ScrollView >
    <StackLayout x:Name="Scroll" Padding = "20"/>
  </ScrollView>

The Content of the Stacklayout should be allowed to take as much space as required. And I would like to scroll the Content.

On the IOS Simulator it works perfectly - I can scroll through the StackLayout. But on my device the scroll doesn't work.

Am I doing sth wrong?
Regards
Julian