Hello I am trying to save in Unreal but keep getting this error message. Don't know where to go from here?,Hello, I am trying to save In unreal but I am unable to and keep getting this error message

Can’t save …/…/…/…/…/…/Bugman/Documents/Unreal Projects/drum_5/Saved/Autosaves/Game/FirstPersonBP/Maps/FirstPersonExampleMap_Auto7.umap: Graph is linked to private object(s) in an external package.
External Object(s):
StaticMeshComponent_2403
StaticMeshComponent_2399
StaticMeshComponent_2396
StaticMeshComponent_2393
StaticMeshComponent_2390

Try to find the chain of references to that object (may take some time)?,