Library Error

I tried to post this in the other help section, but I couldn't figure out how to post it. Does any one know what this means? Any help is welcomed, Thanks.

The Sims 4 Studio - Version 3.1.5.6
System.NullReferenceException: Object reference not set to an instance of an object.
at S4Studio.Shared.ViewModels.Tools.Screenshots.TrayItemVM..ctor(IWindow window, IResourceProvider tray_resources, TrayItemResource tray)
at S4Studio.Shared.ViewModels.Tools.Screenshots.MyLibraryVM.LoadTray()
at S4Studio.UI.Tools.TrayManager..ctor()
at S4Studio.UI.Core.S4SWindowBase.ShowTrayManager()
at S4Studio.ViewModels.GenericUserCommand.<>c__DisplayClass8_0.<.ctor>b__1(Object y)
at S4Studio.ViewModels.GenericUserCommand.Execute(Object parameter)
at MS.Internal.Commands.CommandHelpers.CriticalExecuteCommandSource(ICommandSource commandSource, Boolean userInitiated)
at System.Windows.Controls.MenuItem.InvokeClickAfterRender(Object arg)
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)