NaN error when adding force to direction of near object

To move my character I use addForce(-100, 0, 0) or addForce(100, 0, 0) I won't explain this just watch this video: http://www.mediafire.com/file/ch8otkq3yqpwcst/VID_20180216_120736.mp4 ![alt text][1] [1]: /storage/temp/111405-nan.png