17:46:26.063|Error |Shell |System.NullReferenceException: Object reference not set to an instance of an object. at #=zXIu9xMdtuboHB6GZ6hSSkpyhJPaVt1Bkme7cjSgYXid7yUbpIEBZsr5rq9Z8FJdJEg==.OnDetached() at Ecng.Xaml.Charting.ChartModifiers.ModifierGroup.DetachChild(IChartModifier obj) at Ecng.Xaml.Charting.Common.Extensions.EnumerableExtensions.ForEachDo[T](IEnumerable`1 enumerable, Action`1 operation) at Ecng.Xaml.Charting.ChartModifiers.ModifierGroup.ModifierCollectionChanged(Object sender, NotifyCollectionChangedEventArgs e) at System.Collections.ObjectModel.ObservableCollection`1.OnCollectionChanged(NotifyCollectionChangedEventArgs e) at System.Collections.ObjectModel.ObservableCollection`1.RemoveItem(Int32 index) at System.Collections.ObjectModel.Collection`1.Remove(T item) at System.Collections.Generic.List`1.ForEach(Action`1 action) at Ecng.Xaml.Charting.Common.Maybe.Do[TInput](TInput o, Action`1 action) at #=ztPUCvFrrUbVj6XNqQdK138ZvkB$vQ6KYPPy2gWNPYLFXzIRBPzLK2BFlA8LG.#=z2CKaKvBfSqETZUofs3BBieM=() at StockSharp.Xaml.Charting.ChartArea.set_Chart(IChart #=zN4IWulU=) at StockSharp.Xaml.Charting.Chart.#=zHALikCNcIJFd(ChartArea #=zWbUfl_8=) at StockSharp.Xaml.Charting.Chart.#=zQm7ggYlCwq42() at Ecng.Collections.BaseCollection`2.Clear() at Ecng.Xaml.XamlHelper.GuiAsync(DispatcherObject obj, Action action) at Shell.Strategies.SmaStrategy.SmaStrategy.b__53_0() in F:\Transfer\Shell\Shell\Strategies\SmaStrategy\SmaStrategy.cs:line 169 at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs) at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)