If you're using the Godot 3.2.3, the current stable version, you should be using the corresponding documentation:
https://docs.godotengine.org/en/stable/tutorials/2d/2d_movement.html#click-and-move
It's slightly different, but I'm not sure if that affects its behavior.
I did that tutorial, and it worked correctly.
The behavior you're describing could occur if Sprite is offset from its parent, KinematicBody2D. In the Inspector, make sure that Sprite's Transform >> Position is (0,0).