OsmDroid: TileLoader failed to load tile due to mWriter being null (map shutdown?)

I got OsmDroid log like this:

OsmDroid: TileLoader failed to load tile due to mWriter being null (map shutdown?)

OsmDroid: Tile cache increased from 9 to 24

What is the reason I am getting OsmDroid's log like this

How to fix it?

  // open street map
    implementation 'org.osmdroid:osmdroid-android:6.1.11'

from OsmDroid: TileLoader failed to load tile due to mWriter being null (map shutdown?)