This issue is can be caused by either dirty rear tyres or dirty track.
To properly clean the track, please follow the instruction below. Even if the track is new, please try cleaning the track if you are experiencing this issue. For the best experience, we recommend cleaning the track before and after playing with Anki Drive.
The tyre cleaner can become less effective when being regularly used. To clean the tyre cleaner itself please follow the instruction below.
After cleaning the tyre cleaner, open the tyre cleaner and roll the rear tyres over the sticky part a few times.
Clean tyres should appear even and uniform. Please see the picture below for reference.