Rek'Sai Unburrow on Auto-Attack Bug

This is pretty simple, but I'm not entirely how to recreate this. Sometimes when an enemy is near a wall, when I try to unburrow by auto attacking, it doesn't work and I end up losing the fight because I don't know what's going on. This has happened to me only about four times, but it would be really nice to have a fix on this.

Is fun