Created Unassigned: System.NullReferenceException: Object reference not set to an instance of an object. during ContextMenu.IsOpen = true [11884]

_System.NullReferenceException: Object reference not set to an instance of an object_ during __ContextMenu.IsOpen = true__

at Microsoft.Phone.Controls.ContextMenu.OpenPopup(Point position)
at Microsoft.Phone.Controls.ContextMenu.OnIsOpenChanged(Boolean newValue)
at Microsoft.Phone.Controls.ContextMenu.OnIsOpenChanged(DependencyObject o, DependencyPropertyChangedEventArgs e)
at System.Windows.DependencyObject.RaisePropertyChangeNotifications(DependencyProperty dp, Object oldValue, Object newValue)
at System.Windows.DependencyObject.UpdateEffectiveValue(DependencyProperty property, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, ValueOperation operation)
at System.Windows.DependencyObject.SetValueInternal(DependencyProperty dp, Object value, Boolean allowReadOnlySet)
at System.Windows.DependencyObject.SetValue(DependencyProperty dp, Object value)
at Microsoft.Phone.Controls.ContextMenu.set_IsOpen(Boolean value)
at Yapital.Wallet.PhoneClient.Views.SendMoneyView.UIElement_OnTap(Object sender, GestureEventArgs e)
at MS.Internal.CoreInvokeHandler.InvokeEventHandler(Int32 typeIndex, Delegate handlerDelegate, Object sender, Object args)
at MS.Internal.JoltHelper.FireEvent(IntPtr unmanagedObj, IntPtr unmanagedObjArgs, Int32 argsTypeIndex, Int32 actualArgsTypeIndex, String eventName)