Crashing on import scene with SkeletalMesh

[KENNITHHH]

Using UE4 4.21.3 and exported with Unity 2018.3.7f1

Assertion failed: FindRawBoneIndex(BoneInfo.Name) == INDEX_NONE [File:D:\Build++UE4\Sync\Engine\Source\Runtime\Engine\Public\ReferenceSkeleton.h] [Line: 188]

KERNELBASE
UE4Editor_Core
UE4Editor_Core
UE4Editor_Core
UE4Editor_Engine
UE4Editor_ExodusImport!SkeletalMeshBuilder::setupReferenceSkeleton() [e:\ue4 workshop\schoolabandoned\plugins\exodusimport\source\exodusimport\private\meshbuilder\skeletalmeshbuilder.cpp:89]
UE4Editor_ExodusImport!SkeletalMeshBuilder::setupSkeletalMesh() [e:\ue4 workshop\schoolabandoned\plugins\exodusimport\source\exodusimport\private\meshbuilder\skeletalmeshbuilder.cpp:584]
UE4Editor_ExodusImport!std::_Func_impl_no_alloc<<lambda_727a458e6181fb90e731d8ac45b6e703>,void,USkeletalMesh *>::_Do_call() [c:\program files (x86)\microsoft visual studio\2017\community\vc\tools\msvc\14.16.27023\include\functional:15732480]
UE4Editor_ExodusImport!<lambda_3c5cfe7ee3cb3db104ce1009c30784fa>::operator()() [e:\ue4 workshop\schoolabandoned\plugins\exodusimport\source\exodusimport\private\unrealutilities.h:147]
UE4Editor_ExodusImport!UnrealUtilities::createAssetPackage() [e:\ue4 workshop\schoolabandoned\plugins\exodusimport\source\exodusimport\private\unrealutilities.cpp:20]
UE4Editor_ExodusImport!UnrealUtilities::createAssetObject() [e:\ue4 workshop\schoolabandoned\plugins\exodusimport\source\exodusimport\private\unrealutilities.h:152]
UE4Editor_ExodusImport!JsonImporter::importSkeletalMesh() [e:\ue4 workshop\schoolabandoned\plugins\exodusimport\source\exodusimport\private\jsonimporter\mesh.cpp:100]
UE4Editor_ExodusImport!JsonImporter::importMesh() [e:\ue4 workshop\schoolabandoned\plugins\exodusimport\source\exodusimport\private\jsonimporter\mesh.cpp:124]
UE4Editor_ExodusImport!JsonImporter::loadMeshes() [e:\ue4 workshop\schoolabandoned\plugins\exodusimport\source\exodusimport\private\jsonimporter.cpp:137]
UE4Editor_ExodusImport!JsonImporter::importProject() [e:\ue4 workshop\schoolabandoned\plugins\exodusimport\source\exodusimport\private\jsonimporter\scene.cpp:150]
UE4Editor_ExodusImport!FJsonImportModule::PluginImportButtonClicked() [e:\ue4 workshop\schoolabandoned\plugins\exodusimport\source\exodusimport\private\jsonimport.cpp:145]
UE4Editor_ExodusImport!TBaseRawMethodDelegateInstance<0,FJsonImportModule,void __cdecl(void)>::ExecuteIfSafe() [d:\ue_4.21\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:518]
UE4Editor_Slate
UE4Editor_Slate
UE4Editor_Slate
UE4Editor_Slate
UE4Editor_Slate
UE4Editor_Slate
UE4Editor_Slate
UE4Editor_Slate
UE4Editor_ApplicationCore
UE4Editor_ApplicationCore
UE4Editor_ApplicationCore
UE4Editor_ApplicationCore
user32
user32
UE4Editor_ApplicationCore
UE4Editor
UE4Editor
UE4Editor
UE4Editor
UE4Editor
kernel32
ntdll