Unresolved external for RemoveFromDeferredUpdateList()

I’m trying to add my own Resource derived from FDeferredUpdateResource , but on linking I get unresolved externals on its functions:

1>     Creating library U:\WorkProjects\SeaCraft\Plugins\VaQuoleUI\Intermediate/Build/Win64\Dynamic\UE4Editor\Development\UE4Editor-VaQuoleUIPlugin.lib and object U:\WorkProjects\SeaCraft\Plugins\VaQuoleUI\Intermediate/Build/Win64\Dynamic\UE4Editor\Development\UE4Editor-VaQuoleUIPlugin.exp
1>VaQuoleUIComponent.cpp.obj : error LNK2019: unresolved external symbol "protected: void __cdecl FDeferredUpdateResource::AddToDeferredUpdateList(bool)" (?AddToDeferredUpdateList@FDeferredUpdateResource@@IEAAX_N@Z) referenced in function "public: virtual void __cdecl FVaQuoleResource::InitDynamicRHI(void)" (?InitDynamicRHI@FVaQuoleResource@@UEAAXXZ)
1>VaQuoleUIComponent.cpp.obj : error LNK2019: unresolved external symbol "protected: void __cdecl FDeferredUpdateResource::RemoveFromDeferredUpdateList(void)" (?RemoveFromDeferredUpdateList@FDeferredUpdateResource@@IEAAXXZ) referenced in function "public: virtual void __cdecl FVaQuoleResource::ReleaseDynamicRHI(void)" (?ReleaseDynamicRHI@FVaQuoleResource@@UEAAXXZ)
1>U:\WorkProjects\SeaCraft\Plugins\VaQuoleUI\Binaries\Win64\UE4Editor-VaQuoleUIPlugin.dll : fatal error LNK1120: 2 unresolved externals

What can be a problem with it?