Crash when importing new mesh and regenerating skeleton for additive animation

Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:E:\UE4_Release-413\Engine\Source\Runtime\Core\Public\Containers\Array.h] [Line: 833] Array index out of bounds: 68 from an array of size 68
UE4Editor_Engine!FBoneContainer::GetCompactPoseIndexFromSkeletonIndex() bonecontainer.h:245 
UE4Editor_Engine!UAnimSequence::GetBonePose() animsequence.cpp:1170 
UE4Editor_Engine!UAnimSequence::GetAnimationPose() animsequence.cpp:977 
UE4Editor_Engine!FAnimSingleNodeInstanceProxy::Evaluate() animsinglenodeinstanceproxy.cpp:65 
UE4Editor_AnimGraph!FAnimPreviewInstanceProxy::Evaluate() animpreviewinstance.cpp:129 
UE4Editor_Engine!FAnimInstanceProxy::EvaluateAnimation() animinstanceproxy.cpp:774 
UE4Editor_Engine!UAnimInstance::ParallelEvaluateAnimation() animinstance.cpp:553 
UE4Editor_Engine!USkeletalMeshComponent::EvaluateAnimation() skeletalmeshcomponent.cpp:1113 
UE4Editor_Engine!USkeletalMeshComponent::PerformAnimationEvaluation() skeletalmeshcomponent.cpp:1174 
UE4Editor_Engine!USkeletalMeshComponent::RefreshBoneTransforms() skeletalmeshcomponent.cpp:1351 
UE4Editor_UnrealEd!UDebugSkelMeshComponent::RefreshBoneTransforms() debugskelmeshcomponent.cpp:418 
UE4Editor_Engine!USkinnedMeshComponent::TickComponent() skinnedmeshcomponent.cpp:546 
UE4Editor_Engine!USkeletalMeshComponent::TickComponent() skeletalmeshcomponent.cpp:765 
UE4Editor_UnrealEd!UDebugSkelMeshComponent::TickComponent() debugskelmeshcomponent.cpp:735 
UE4Editor_Engine!FActorComponentTickFunction::ExecuteTickHelper<<lambda_aa79ebd94b2c9e6b2d520765e2e11e5e> >() actor.h:2937 
UE4Editor_Engine!FActorComponentTickFunction::ExecuteTick() actorcomponent.cpp:707 
UE4Editor_Engine!FTickFunctionTask::DoTask() ticktaskmanager.cpp:251 
UE4Editor_Engine!TGraphTask<FTickFunctionTask>::ExecuteTask() taskgraphinterfaces.h:868 
UE4Editor_Core!FNamedTaskThread::ProcessTasksNamedThread() taskgraph.cpp:932 
UE4Editor_Core!FNamedTaskThread::ProcessTasksUntilQuit() taskgraph.cpp:679 
UE4Editor_Core!FTaskGraphImplementation::WaitUntilTasksComplete() taskgraph.cpp:1776 
UE4Editor_Engine!FTickTaskSequencer::ReleaseTickGroup() ticktaskmanager.cpp:520 
UE4Editor_Engine!FTickTaskManager::RunTickGroup() ticktaskmanager.cpp:1429 
UE4Editor_Engine!UWorld::RunTickGroup() leveltick.cpp:706 
UE4Editor_Engine!UWorld::Tick() leveltick.cpp:1282 
UE4Editor_Persona!FAnimationViewportClient::Tick() animationeditorviewportclient.cpp:718 
UE4Editor_UnrealEd!UEditorEngine::Tick() editorengine.cpp:1476 
UE4Editor_UnrealEd!UUnrealEdEngine::Tick() unrealedengine.cpp:371 
UE4Editor!FEngineLoop::Tick() launchengineloop.cpp:2834 
UE4Editor!GuardedMain() launch.cpp:156 
UE4Editor!GuardedMainWrapper() launchwindows.cpp:126 
UE4Editor!WinMain() launchwindows.cpp:202 
UE4Editor!__scrt_common_main_seh() exe_common.inl:264 
kernel32!<Unknown> 
ntdll!<Unknown>