ObjectLookup and NetGUIDLookup size growth constantly

ObjectLookup and NetGUIDLookup only clean up in function PostSeamlessTravelGarbageCollect ,

but when a lots of actors spawned and destroyed, that two Map will Increase to a big size, and cause memory problem, is there any way to clean them?

when i call CleanPackageMaps in PostGarbageCollect Function, it will cause crash!