Download Duplicated AssetBundle in Android Marshmellow device

I have android 6.0 Marshmellow device (api23)

(ex - Nexus5, 6, 9)

This is my step

1. Start App

2. Download AssetBundle

3. Exit App

4. Setting -> Application -> My app -> App Permission -> Storage Permission Change

5. ReStart App

6. Download Duplicated AssetBundle

Finally, Confirm App Storage -> double storage number ex) Default App Storage 50MB, AssetBundle 100MB -> 250MB (50 + 100 *2)

I try changing unity build Setting in Install Location, Write Access. but same issue...

I try deleting android menifest file's External Storage. but same issue...

How do i change?

please help me.