Reports

The Route property in the Flyout seems to be the issue. Hopefully somebody who knows a lot more about it will explain in the comments? ;)

<FlyoutItem FlyoutDisplayOptions="AsMultipleItems">

    <ShellContent
        Title="Page 1"
        Icon="one_icon.png"
        ContentTemplate="{DataTemplate local:OnePage}"
        ** Route="OnePage" />  <!-- << I believe this is the fault--> **
    <ShellContent
        Title="Page 2"
        Icon="two_icon.png"
        ContentTemplate="{DataTemplate local:TwoPage}"
        ** Route="TwoPage" />  <!-- << Delete this --> **
    <ShellContent
        Title="Page 3"
        Icon="three_icon.png"
        ContentTemplate="{DataTemplate local:ThreePage}"
        IsVisible="true"
        ** Route="ThreePage" /> <!-- << Delete this --> **

</FlyoutItem>

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