UE4.24 crash 01

LoginId:3df23dce4af146e87009a6aaca0b673a
EpicAccountId:8b8c0e9040294c3e997b7dabf803fa6f

LowLevelFatalError [File:C:\Dev\SFL\trunk\Source\SFL\SFLGameModeBase.h] [Line: 83] Pure virtual not implemented (ASFLGameModeBase::GetType)

UE4Editor_SFL!ASFLGameModeBase::GetType() [c:\dev\sfl\trunk\source\sfl\sflgamemodebase.h:83]
UE4Editor_SFL!ASFLGameModeBase::InitGameState() [c:\dev\sfl\trunk\source\sfl\sflgamemodebase.cpp:781]
UE4Editor_Engine!AGameModeBase::PreInitializeComponents() [c:\dev\ue4-work-in-progress\engine\source\runtime\engine\private\gamemodebase.cpp:125]
UE4Editor_Engine!ULevel::RouteActorInitialize() [c:\dev\ue4-work-in-progress\engine\source\runtime\engine\private\level.cpp:1742]
UE4Editor_Engine!UWorld::InitializeActorsForPlay() [c:\dev\ue4-work-in-progress\engine\source\runtime\engine\private\world.cpp:4033]
UE4Editor_Engine!UGameInstance::StartPlayInEditorGameInstance() [c:\dev\ue4-work-in-progress\engine\source\runtime\engine\private\gameinstance.cpp:401]
UE4Editor_UnrealEd!UEditorEngine::CreatePIEGameInstance() [c:\dev\ue4-work-in-progress\engine\source\editor\unrealed\private\playlevel.cpp:3570]
UE4Editor_UnrealEd!UEditorEngine::PlayInEditor() [c:\dev\ue4-work-in-progress\engine\source\editor\unrealed\private\playlevel.cpp:2613]
UE4Editor_UnrealEd!UEditorEngine::StartQueuedPlayMapRequest() [c:\dev\ue4-work-in-progress\engine\source\editor\unrealed\private\playlevel.cpp:1303]
UE4Editor_UnrealEd!UEditorEngine::Tick() [c:\dev\ue4-work-in-progress\engine\source\editor\unrealed\private\editorengine.cpp:1600]
UE4Editor_UnrealEd!UUnrealEdEngine::Tick() [c:\dev\ue4-work-in-progress\engine\source\editor\unrealed\private\unrealedengine.cpp:410]
UE4Editor!FEngineLoop::Tick() [c:\dev\ue4-work-in-progress\engine\source\runtime\launch\private\launchengineloop.cpp:4485]
UE4Editor!GuardedMain() [c:\dev\ue4-work-in-progress\engine\source\runtime\launch\private\launch.cpp:173]
UE4Editor!GuardedMainWrapper() [c:\dev\ue4-work-in-progress\engine\source\runtime\launch\private\windows\launchwindows.cpp:134]
UE4Editor!WinMain() [c:\dev\ue4-work-in-progress\engine\source\runtime\launch\private\windows\launchwindows.cpp:263]
UE4Editor!__scrt_common_main_seh() [d:\agent\_work\2\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
kernel32
ntdll