Sprite Atlas not recreate when move textures to another folder

unity version is 2018.4.0.f1 LTS

I have 2 Sprite Atlas named Atlas_A and Atlas B.

Atlas_A Objects for Packing included a folder name A. Atlas_B Objects for Packing included a folder name B.

I attached them to 2 objects and make sure only 2 Atlas in memory.(Frame Debug)

but if I move all textures from folder B to folder A. It should be only one (Atlas_A) atlas in memory.

but It is not work, every new moved textures are individual Draw Mesh.

I think sprite caches are not update when moving textures.

if I changed textures format or other data in Texture Importer , It works well.

so how should I solved this issue?