Warning when create Actor from Template In Level

When create a Actor From Template in level ,the Template is a BP_Actor, with PrimitiveComponent created in BP attached to RootComponent, and the RootComponent is created by c++,Warning occurs

Gamethread hitch waiting for resource cleanup on a UObject (%s) overwrite took %6.2fms. Fix the higher level code so that this does not happen.

In ActorConstruction.cpp ,function ExecuteConstruction, I found SimpleConstructionScript’s RootNodes are PrimitiveComponents but not the RootComponent, it will construct the childComponents and then destroy them , but detachfence is preventing this destroy
In Editor mode, the warning is skipped, How to Deal this problem?