Fix to address book

prs.desktop/DockPanels/ContactDock.xaml.cs

@@ -7,7 +7,7 @@ namespace PRSDesktop
     /// </summary>
     public partial class ContactDock : UserControl, IDockPanel
     {
-        private ContactGrid _contacts;
+        private ContactGrid? _contacts;
 
         public ContactDock()
         {
@@ -18,11 +18,12 @@ namespace PRSDesktop
         {
             _contacts = new ContactGrid();
             Content = _contacts;
+            _contacts.Refresh(true, false);
         }
         
         public void Refresh()
         {
-            _contacts.Refresh(false, true);
+            _contacts?.Refresh(false, true);
         }
     }
 }