ToolBox elements in axml not displaying after build+deploy

Hi guys, I've just started learning xamarin and don't understand why my changes to the UI using the designer in axml does not display after i save and deploy. I'm using android 6.0 on Visual studio.

I've checked the actual Main.xaml and it shows the code has been added when I dragged and dropped the button: However the chosen colours from designer doesn't apply.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:minWidth="25px"
    android:minHeight="25px"
              >
    <Button
        android:text="Button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/button1" />
</LinearLayout>

Is there anything else I was supposed to add to get this to work ? any help will be appreciated.